85. main(){

int i=10,j=20;

j = i, j?(i,j)?i:j:j;

printf("%d %d",i,j);

}

Answer:

10 10

Explanation:

The Ternary operator ( ? : ) is equivalent for if-then-else statement. So the question can be written as:

if(i,j){

if(i,j)

j = i;

else

j = j;

}

else

j = j;

86. 1. const char *a;

2. char* const a;

3. char const *a;

-Differentiate the above declarations.

Answer:

1. 'const' applies to char * rather than 'a' ( pointer to a constant char )

*a='F' : illegal

a="Hi" : legal

2. 'const' applies to 'a' rather than to the value of a (constant pointer to char )

*a='F' : legal

a="Hi" : illegal

3. Same as 1.

87. main(){

int i=5,j=10;

i=i&=j&&10;

printf("%d %d",i,j);

}

Answer:

1 10

Explanation:

The expression can be written as i=(i&=(j&&10)); The inner expression (j&&10) evaluates to 1 because j==10. i is 5. i = 5&1 is 1. Hence the result.

88. main(){

int i=4,j=7;

j = j || i++ && printf("YOU CAN");

printf("%d %d", i, j);

}

Answer:

4 1

Explanation:

The boolean expression needs to be evaluated only till the truth value of the expression is not known. j is not equal to zero itself means that the expression’s truth value is 1. Because it is followed by || and true || (anything) => true where (anything) will not be evaluated. So the remaining expression is not evaluated and so the value of i remains the same.

Similarly when && operator is involved in an expression, when any of the operands become false, the whole expression’s truth value becomes false and hence the remaining expression will not be evaluated.

false && (anything) => false where (anything) will not be evaluated.

89. main(){

register int a=2;

printf("Address of a = %d",&;

printf("Value of a = %d",;

}

Answer:

Compier Error: '&' on register variable

Rule to Remember:

& (address of ) operator cannot be applied on register variables.

90. main(){

float i=1.5;

switch(i){

case 1: printf("1");

case 2: printf("2");

default : printf("0");

}

Answer:

Compiler Error: switch expression not integral

Explanation:

Switch statements can be applied only to integral types.

91. main(){

extern i;

printf("%d\n",i);{

int i=20;

printf("%d\n",i);

}

Answer:

Linker Error : Unresolved external symbol i

Explanation:

The identifier i is available in the inner block and so using extern has no use in resolving it.

92. main(){

int a=2,*f1,*f2;

f1=f2=&a;

*f2+=*f2+=a+=2.5;

printf("\n%d %d %d",a,*f1,*f2);

}

Answer:

16 16 16

Explanation:

f1 and f2 both refer to the same memory location a. So changes through f1 and f2 ultimately affects only the value of a.

93. main(){

char *p="GOOD";

char a[ ]="GOOD";

printf("\n sizeof(p) = %d, sizeof(*p) = %d, strlen(p) = %d", sizeof(p), sizeof(*p), strlen(p));

printf("\n sizeof( = %d, strlen( = %d", sizeof(, strlen();

}

Answer:

sizeof(p) = 2, sizeof(*p) = 1, strlen(p) = 4

sizeof( = 5, strlen( = 4

Explanation:

sizeof(p) => sizeof(char*) => 2

sizeof(*p) => sizeof(char) => 1

Similarly,

sizeof( => size of the character array => 5

When sizeof operator is applied to an array it returns the sizeof the array and it is not the same as the sizeof the pointer variable. Here the sizeof( where a is the character array and the size of the array is 5 because the space necessary for the terminating NULL character should also be taken into account.

94. #define DIM( array, type) sizeof(array)/sizeof(type)

main(){

int arr[10];

printf(“The dimension of the array is %d”, DIM(arr, int));

}

Answer:

Explanation:

The size of integer array of 10 elements is 10 * sizeof(int). The macro expands to sizeof(arr)/sizeof(int) => 10 * sizeof(int) / sizeof(int) => 10.

95. int DIM(int array[]) {

return sizeof(array)/sizeof(int );

}

main(){

int arr[10];

printf(“The dimension of the array is %d”, DIM(arr));

}

Answer:

Explanation:

Arrays cannot be passed to functions as arguments and only the pointers can be passed. So the argument is equivalent to int * array (this is one of the very few places where [] and * usage are equivalent). The return statement becomes, sizeof(int *)/ sizeof(int) that happens to be equal in this case.

96. main(){

static int a[3][3]={1,2,3,4,5,6,7,8,9};

int i,j;

static *p[]={a,a+1,a+2};

for(i=0;i<3;i++){

for(j=0;j<3;j++)

printf("%d\t%d\t%d\t%d\n",*(*(p+i)+j),

*(*(j+p)+i),*(*(i+p)+j),*(*(p+j)+i));

}

Answer:

1 1 1 1

2 4 2 4

3 7 3 7

4 2 4 2

5 5 5 5

6 8 6 8

7 3 7 3

8 6 8 6

9 9 9 9

Explanation:

*(*(p+i)+j) is equivalent to p[i][j].

97. main(){

void swap();

int x=10,y=8;

swap(&x,&y);

printf("x=%d y=%d",x,y);

}

void swap(int *a, int *b){

*a ^= *b, *b ^= *a, *a ^= *b;

}

Answer:

x=10 y=8

Explanation:

Using ^ like this is a way to swap two variables without using a temporary variable and that too in a single statement.

Inside main(), void swap(); means that swap is a function that may take any number of arguments (not no arguments) and returns nothing. So this doesn’t issue a compiler error by the call swap(&x,&y); that has two arguments.

This convention is historically due to pre-ANSI style (referred to as Kernighan and Ritchie style) style of function declaration. In that style, the swap function will be defined as follows,

void swap()

int *a, int *b{

*a ^= *b, *b ^= *a, *a ^= *b;

}

where the arguments follow the (). So naturally the declaration for swap will look like, void swap() which means the swap can take any number of arguments.

98. main(){

int i = 257;

int *iPtr = &i;

printf("%d %d", *((char*)iPtr), *((char*)iPtr+1) );

}

Answer:

1 1

Explanation:

The integer value 257 is stored in the memory as, 00000001 00000001, so the individual bytes are taken by casting it to char * and get printed.

99. main(){

int i = 258;

int *iPtr = &i;

printf("%d %d", *((char*)iPtr), *((char*)iPtr+1) );

}

Answer:

2 1

Explanation:

The integer value 257 can be represented in binary as, 00000001 00000001. Remember that the INTEL machines are ‘small-endian’ machines. Small-endian means that the lower order bytes are stored in the higher memory addresses and the higher order bytes are stored in lower addresses. The integer value 258 is stored in memory as: 00000001 00000010.

100.main(){

int i=300;

char *ptr = &i;

*++ptr=2;

printf("%d",i);

}

Answer:

556

Explanation:

The integer value 300 in binary notation is: 00000001 00101100. It is stored in memory (small-endian) as: 00101100 00000001. Result of the expression *++ptr = 2 makes the memory representation as: 00101100 00000010. So the integer corresponding to it is 00000010 00101100 => 556.

101.main()

{

char * str = "hello";

char * ptr = str;

char least = 127;

while (*ptr++)

least = (*ptr

printf("%d",least);

}

Answer:

Explanation:

After ‘ptr’ reaches the end of the string the value pointed by ‘str’ is ‘\0’. So the value of ‘str’ is less than that of ‘least’. So the value of ‘least’ finally is 0.

102.

Declare an array of N pointers to functions returning pointers to functions returning pointers to characters?

Answer:

(char*(*)( )) (*ptr[N])( );

103.main(){

struct student {

char name[30];

struct date dob;

}stud;

struct date{

int day,month,year;

};

scanf("%s%d%d%d", stud.rollno, &student.dob.day, &student.dob.month, &student.dob.year);

}

Answer:

Compiler Error: Undefined structure date

Explanation:

Inside the struct definition of ‘student’ the member of type struct date is given. The compiler doesn’t have the definition of date structure (forward reference is not allowed in C in this case) so it issues an error.

104.main(){

struct date;

struct student{

char name[30];

struct date dob;

}stud;

struct date{

int day,month,year;

};

scanf("%s%d%d%d", stud.rollno, &student.dob.day, &student.dob.month, &student.dob.year);

}

Answer:

Compiler Error: Undefined structure date

Explanation:

Only declaration of struct date is available inside the structure definition of ‘student’ but to have a variable of type struct date the definition of the structure is required.

105.

There were 10 records stored in “somefile.dat” but the following program printed 11 names. What went wrong?

void main(){

struct student{

char name[30], rollno[6];

}stud;

FILE *fp = fopen(“somefile.dat”,”r”);

while(!feof(fp)) {

fread(&stud, sizeof(stud), 1 , fp);

puts(stud.name);

}

Explanation:

fread reads 10 records and prints the names successfully. It will return EOF only when fread tries to read another record and fails reading EOF (and returning EOF). So it prints the last record again. After this only the condition feof(fp) becomes false, hence comes out of the while loop.

106.Is there any difference between the two declarations,

1. int foo(int *arr[]) and

2. int foo(int *arr[2])

Answer:

Explanation:

Functions can only pass pointers and not arrays. The numbers that are allowed inside the [] is just for more readability. So there is no difference between the two declarations.

107.What is the subtle error in the following code segment?

void fun(int n, int arr[]){

int *p=0;

int i=0;

while(i++

p = &arr[i];

*p = 0;

}

Answer & Explanation:

If the body of the loop never executes p is assigned no address. So p remains NULL where *p =0 may result in problem (may rise to runtime error “NULL pointer assignment” and terminate the program).

108.What is wrong with the following code?

int *foo(){

int *s = malloc(sizeof(int)100);

assert(s != NULL);

return s;

}

Answer & Explanation:

assert macro should be used for debugging and finding out bugs. The check s != NULL is for error/exception handling and for that assert shouldn’t be used. A plain if and the corresponding remedy statement has to be given.

109.What is the hidden bug with the following statement?

assert(val++ != 0);

Answer & Explanation:

Assert macro is used for debugging and removed in release version. In assert, the experssion involves side-effects. So the behavior of the code becomes different in case of debug version and the release version thus leading to a subtle bug.

Rule to Remember:

Don’t use expressions that have side-effects in assert statements.

110.void main(){

int *i = 0x400; // i points to the address 400

*i = 0; // set the value of memory location pointed by i;

}

Answer:

Undefined behavior

Explanation:

The second statement results in undefined behavior because it points to some location whose value may not be available for modification. This type of pointer in which the non-availability of the implementation of the referenced location is known as 'incomplete type'.

111.#define assert(cond) if(!(cond)) \

(fprintf(stderr, "assertion failed: %s, file %s, line %d \n",#cond,\

__FILE__,__LINE__), abort())

void main(){

int i = 10;

if(i==0)

assert(i < 100);

else

printf("This statement becomes else for if in assert macro");

}

Answer:

No output

Explanation:

The else part in which the printf is there becomes the else for if in the assert macro. Hence nothing is printed. The solution is to use conditional operator instead of if statement

#define assert(cond) ((cond)?(0): (fprintf (stderr, "assertion failed: \ %s, file %s, line %d \n",#cond, __FILE__,__LINE__), abort()))

Note:

However this problem of “matching with nearest else” cannot be solved by the usual method of placing the if statement inside a block like this,

#define assert(cond) { \

if(!(cond)) \

(fprintf(stderr, "assertion failed: %s, file %s, line %d \n",#cond,\

__FILE__,__LINE__), abort()) \

}

112.Is the following code legal?

struct a {

int x;

struct a b;

}

Answer:

Explanation:

Is it not legal for a structure to contain a member that is of the same type as in this case. Because this will cause the structure declaration to be recursive without end.

113.Is the following code legal?

struct a {

int x;

struct a *b;

}

Answer:

Yes.

Explanation:

*b is a pointer to type struct a and so is legal. The compiler knows, the size of the pointer to a structure even before the size of the structure is determined(as you know the pointer to any type is of same size). This type of structures is known as ‘self-referencing’ structure.

114.Is the following code legal?

typedef struct a {

int x;

aType *b;

}aType;

Answer:

Explanation:

The typename aType is not known at the point of declaring the structure (forward references are not made for typedefs).

115.Is the following code legal?

typedef struct a aType;

struct a{

int x;

aType *b;

};

Answer:

Yes

Explanation:

The typename aType is known at the point of declaring the structure, because it is already typedefined.

116.Is the following code legal?

void main(){

typedef struct a aType;

aType someVariable;

struct a {

int x;

aType *b;

};

}

Answer:

Explanation:

When the declaration,typedef struct a aType; is encountered body of struct a is not known. This is known as ‘incomplete types’.

117.void main(){

printf(“sizeof (void *) = %d \n“, sizeof( void *));

printf(“sizeof (int *) = %d \n”, sizeof(int *));

printf(“sizeof (double *) = %d \n”, sizeof(double *));

printf(“sizeof(struct unknown *) = %d \n”, sizeof(struct unknown *));

}

Answer:

sizeof (void *) = 2

sizeof (int *) = 2

sizeof (double *) = 2

sizeof(struct unknown *) = 2

Explanation:

The pointer to any type is of same size.

118.char inputString[100] = {0};

To get string input from the keyboard which one of the following is better?

1) gets(inputString)

2) fgets(inputString, sizeof(inputString), fp)

Answer & Explanation:

The second one is better because gets(inputString) doesn't know the size of the string passed and so, if a very big input (here, more than 100 chars) the charactes will be written past the input string. When fgets is used with stdin performs the same operation as gets but is safe.

119.Which version do you prefer of the following two,

1) printf(“%s”,str); // or the more curt one

2) printf(str);

Answer & Explanation:

Prefer the first one. If the str contains any format characters like %d then it will result in a subtle bug.

120.void main(){

int i=10, j=2;

int *ip= &i, *jp = &j;

int k = *ip/*jp;

printf(“%d”,k);

}

Answer:

Compiler Error: “Unexpected end of file in comment started in line 5”.

Explanation:

The programmer intended to divide two integers, but by the “maximum munch” rule, the compiler treats the operator sequence / and * as /* which happens to be the starting of comment. To force what is intended by the programmer,

int k = *ip/ *jp;

// give space explicity separating / and *

//or

int k = *ip/(*jp);

// put braces to force the intention

will solve the problem.

121.void main(){

char ch;

for(ch=0;ch<=127;ch++)

printf(“%c %d \n“, ch, ch);

}

Answer:

Implementaion dependent

Explanation:

The char type may be signed or unsigned by default. If it is signed then ch++ is executed after ch reaches 127 and rotates back to -128. Thus ch is always smaller than 127.

122.Is this code legal?

int *ptr;

ptr = (int *) 0x400;Answer:

Yes

Explanation:

The pointer ptr will point at the integer in the memory location 0x400.

123.main(){

char a[4]="HELLO";

printf("%s",;

}

Answer:

Compiler error: Too many initializers

Explanation:

The array a is of size 4 but the string constant requires 6 bytes to get stored.

124.main(){

char a[4]="HELL";

printf("%s",;

}

Answer:

HELL%@!~@!@???@~~!

Explanation:

The character array has the memory just enough to hold the string “HELL” and doesnt have enough space to store the terminating null character. So it prints the HELL correctly and continues to print garbage values till it accidentally comes across a NULL character.

125.main(){

int a=10,*j;

void *k;

j=k=&a;

j++;

k++;

printf("\n %u %u ",j,k);

}

Answer:

Compiler error: Cannot increment a void pointer

Explanation:

Void pointers are generic pointers and they can be used only when the type is not known and as an intermediate address storage type. No pointer arithmetic can be done on it and you cannot apply indirection operator (*) on void pointers.

126.Printf can be implemented by using __________ list.

Answer:

Variable length argument lists

127. char *someFun(){

char *temp = “string constant";

return temp;

}

int main(){

puts(someFun());

}

Answer:

string constant

Explanation:

The program suffers no problem and gives the output correctly because the character constants are stored in code/data area and not allocated in stack, so this doesn’t lead to dangling pointers.

128.char *someFun1(){

char temp[ ] = “string";

return temp;

}

char *someFun2(){

char temp[ ] = {‘s’, ‘t’,’r’,’i’,’n’,’g’};

return temp;

}

int main(){

puts(someFun1());

puts(someFun2());

}

Answer:

Garbage values.

Explanation:

Both the functions suffer from the problem of dangling pointers. In someFun1() temp is a character array and so the space for it is allocated in heap and is initialized with character string “string”. This is created dynamically as the function is called, so is also deleted dynamically on exiting the function so the string data is not available in the calling function main() leading to print some garbage values. The function someFun2() also suffers from the same problem but the problem can be easily identified in this case.

129.Explain Internal linkage.

Internal linkage means that all declarations of the identifier within one source file refer to a single entity but declarations of the same identifier in other source files refer to different entities.

130.Can the formal parameter to a function be declared static?

No, because arguments are always passed on the stack to support recursion.

131.What is an lvalue?

Something that can appear on the left side of the "=" sign, it identifies a place where the result can be stored. For example, in the equation a=b+25, a is an lvalue.

In the equation b+25=a, b+25 cannot be used as an lvalue, because it does not identify a specific place. Hence the above assignment is illegal.

132.Every expression that is an lvalue, is also an rvalue. Is the reverse true?

No, lvalue denotes a place in the computer's memory. An rvalue denotes a value, so it can only be used on the right hand side of an assignment.

133.What happens if indirection is performed on a NULL pointer?

On some machines the indirection accesses the memory location zero. On other machines indirection on a NULL pointer cause a fault that terminate the program. Hence the result is implementation dependent.

134.Is the statement legal? d=10-*d.

Illegal because it specifies that an integer quantity (10-*d) be stored in a pointer variable

135.What does the below indicate?

int *func(void)

a. void indicates that there aren't any arguments.

b. there is one argument of type void.

Answer: a

136.What are data type modifiers?

To extend the data handling power, C adds 4 modifiers which may only be applied to char and int. They are namely signed, unsigned, long and short. Although long may also be applied to double.

137.Interpret the meaning of the following.

a. “ab”,”a+b”

b. “w+t”

Answer:

"ab","a+b"->open a binary file for appending

"w+t" ->create a text file for reading and writing.

138.What is NULL in the context of files?

In using files, if any error occurs, a NULL pointer is returned.

139.What is Register storage class?

It concerns itself with storing data in the registers of the microprocessor and not in memory. The value of the variable doesn't have to be loaded freshly from memory every time. It's important to realize that this a request to the compiler and not a directive. The compiler may not be able to do it. Since the registers are normally of 16 bits long, we can use the register storage class for ints and char's.

140.What is an assertion statement?

They are actually macros. They test statements you pass to them and if the statement is false, they halt the program and inform you that the assertion failed. It is defined in the header file .

141.Parse int *(*(*(*abc)())[6])();

abc is a pointer to a function returning a pointer to array of pointer to functions returning pointer to integer.

1. The C language terminator is
        (a) semicolon                        (b) colon                        (c) period                                 (d) exclamation mark   ans:a)
2. What is false about the following -- A compound statement is
        (a) A set of simple statements           (b) Demarcated on either side by curly brackets
        (c) Can be used in place of simple statement (d) A C function is not a compound statement.
Ans)c
3. What is true about the following C Functions
        (a) Need not return any value           (b) Should always return an integer
        (c) Should always return a float        (d) Should always return more than one value
Ans) a
4. Main must be written as
        (a) The first function in the program              (b) Second function in the program
        (c) Last function in the program                     (d) Any where in the program
Ans)d
5. Which of the following about automatic variables within a function is correct ?
        (a) Its type must be declared before using the variable    (b) They are local
        (c) They are not initialized to zero                                     (d) They are global
Ans)a?
6. Write one statement equivalent to the following two statements:   x=sqr(a); return(x);
    Choose from one of the alternatives
        (a) return(sqr(a));                                    (b) printf("sqr(a)");
        (c) return(a*a*a);                                    (d) printf("%d",sqr(a));
Ans)a
7. Which of the following about the C comments is incorrect ?
        (a) Comments can go over multiple lines
        (b) Comments can start any where in the line
        (c) A line can contain comments with out any language statements
        (d) Comments can occur within comments
Ans)d nested comments are not allowed
8. What is the value of y in the following code?
                            x=7;
                            y=0;
                            if(x=6) y=7;
                            else y=1;
        (a) 7                                    (b) 0                                (c) 1                                 (d) 6
Ans)a used = instead of ==
9. Read the function conv() given below
                            conv(int t)
                            {
                                int u;
                                u=5/9 * (t-32);
                                return(u);
                            }
    What is returned
        (a) 15                                    (b) 0                                (c) 16.1                            (d) 29
10. Which of the following represents true statement either x is in the range of 10 and 50 or y is zero
        (a) x >=10 && x <= 50 || y = = 0                                (b) x<50
        (c) y!=10 && x >= 50                                                    (d) None of these
Ans)a
11. Which of the following is not an infinite loop ?
        (a) while(1)\{ ....}                                                    (b) for(;;){...}
        (c) x=0;                                                                   (d) # define TRUE 0
            do{ /*x unaltered within the loop*/                                ...
                .....}while(x = = 0);                                                while(TRUE){ ....}

Ans)b?
12. What does the following function print?
                            func(int i)
                            {
                                if(i%2)return 0;
                                else return 1;
                            }
                            main()
                            {
                                int =3;
                                i=func(i);
                                i=func(i);
                                printf("%d",i);
                            }
        (a) 3                                (b) 1                                (c) 0                                (d) 2
13. How does the C compiler interpret the following two statements
                     p=p+x;
                     q=q+y;
        (a) p= p+x;            (b)p=p+xq=q+y;       (c)p= p+xq;      (d)p=p+x/q=q+y;
             q=q+y;                                                                    q=q+y;

For questions 14,15,16,17 use the following alternatives:
        a.int                                 b.char                                 c.string                              d.float
14. '9'
15. "1 e 02"
16. 10e05
17. 15
18. Read the folllowing code
        # define MAX 100
        # define MIN 100
        ....
        ....
            if(x>MAX)
                x=1;
            else if(x                 x=-1;
                x=50;
if the initial value of x=200,what is the value after executing this code?
        (a) 200                                (b) 1                                (c) -1                                (d) 50

19. A memory of 20 bytes is allocated to a string declared as char *s then the following two statements are executed:
                        s="Entrance"
                        l=strlen(s);
        what is the value of l ?
        (a)20                                (b)8                                (c)9                                (d)21

20. Given the piece of code
                int a[50];
                int *pa;
                pa=a;
        To access the 6th element of the array which of the following is incorrect?
        (a) *(a+5)                                (b) a[5]                     (c) pa[5]                           (d) *(*pa + 5}
Ans)a
21. Consider the following structure:
                            struct num nam
                            {
                                int no;
                                char name[25];
                            }
                            struct num nam n1[]={{12,"Fred"},{15,"Martin"},{8,"Peter"},{11,Nicholas"}};
                            .....
                            .....
                            printf("%d%d",n1[2],no,(*(n1 + 2),no) + 1);
    What does the above statement print?
        (a) 8,9                            (b) 9,9                            (c) 8,8                            (d) 8,unpredictable value

22. Identify the in correct expression
       (a)a=b=3=4;               (b)a=b=c=d=0;                (c)float a=int b= 3.5;        (d)int a; floatb;a=b=3.5;
Ans) b

23. Regarding the scope of the varibles;identify the incorrect statement:
(a) automatic variables are automatically initialized to 0    (b) static variables are are automatically initialized to 0
(c) the address of a register variable is not accessible       (d) static variables cannot be initialized with any expression

24. cond 1?cond 2?cond 3?:exp 1:exp 2:exp 3:exp 4;
is equivalent to which of the following?
                (a) if cond 1
                    exp 1;
                    else if cond 2
                    exp 2;
                    else if cond 3
                    exp 3;
                    else exp 4;
                (b) if cond 1
                    if cond 2
                    if cond 3
                    exp 1;
                    else exp 2;
                    else exp 3;
                    else exp 4;
                (c) if cond 1 && cond 2 && cond 3
                    exp 1 |exp 2|exp 3|exp 4;
                (d) if cond 3
                    exp 1;
                    else if cond 2 exp 2;
                    else if cond 3 exp 3;
                    else exp 4;
25. The operator for exponentiation is
        (a) **                            (b) ^                            (c) %                            (d) not available

Ans )d
26. Which of the following is invalid
        (a) a+=b                        (b) a*=b                       (c) a>>=b                    (d) a**=b

27. What is y value of the code if input x=10
                            y=5;
                            if (x==10)
                            else if(x==9)
                            else y=8;
        (a)9                            (b)8                                 (c)6                            (d)7

28. What does the following code do?
                            fn(int n, int p, int r)
                            {
                                static int a=p;
                                switch(n)
                                {
                                    case 4:a+=a*r;
                                    case 3:a+=a*r;
                                    case 2:a+=a*r;
                                    case 1:a+=a*r;
                              }
                            }
(a) computes simple interest for one year                (b) computes amount on compound interest for 1 to 4 years
(c) computes simple interest for four year                (d) computes compound interest for 1 year

29.
                            a=0;
                            while(a<5)
                            printf("%d\\n",a++);
    How many times does the loop occurs?
        (a) infinite                                    (b)5                                    (c)4                                    (d)6

Ans)b
30. How many times does the loop iterated ?
                           for(i=0;i=10;i+=2)
                            printf("Hi\\n");
        (a)10                                          (b) 2                                    (c) 5                                   (d) None of these

Ans) d infinite times

31. What is incorrect among the following
        A recursive function
            (a) calls itself                                            (b) is equivalent to a loop
            (c) has a termination condition                  (d) does not have a return value at all
Ans)d
32. Which of the following go out of the loop if expn 2 becoming false
        (a) while(expn 1)\{...if(expn 2)continue;}        (b) while(!expn 1)\{if(expn 2)continue;...}
        (c) do{..if(expn 1)continue;..}while(expn 2);   (d) while(!expn 2)\{if(expn 1)continue;..\}

33. Consider the following program
                            main()
                            {
                                unsigned int i=10;
                                while(i>=0)
                                {
                                    printf("%u",i)
                                    i--;
                                }
                            }
    How many times the loop will get executed
        (a)10                                (b)9                                (c)11                                (d) infinite

34.Pick out the odd one out
        (a) malloc()                       (b) calloc()                     (c) free()                           (d) realloc()
ans) c
35.Consider the following program
                            main()
                            {
                                int a[5]={1,3,6,7,0};
                                int *b;
                                b=&a[2];
                            }
    The value of b[-1] is
        (a) 1                            (b) 3                                (c) -6                                (d) none

36.                       # define prod(a,b)=a*b
                            main()
                            {
                                int x=2;
                                int y=3;
                                printf("%d",prod(x+2,y-10));
                            }
    the output of the program is
        (a) 8                            (b) 6                                (c) 7                                (d) None

37.Consider the following program segment
                            int n,sum=1;
                            switch(n)
                            {
                                case 2:sum=sum+2;
                                case 3:sum*=2;
                                break;
                                default:sum=0;
                            }
    If n=2, what is the value of sum
        (a) 0                            (b) 6                                (c) 3                                    (d) None of these

38. Identify the incorrect one
                1.if(c=1)
                2.if(c!=3)
                3.if(a                 4.if(c==1)
        (a) 1 only                     (b) 1&3                            (c) 3 only                            (d) All of the above

39. The format specified for hexa decimal is
        (a) %d                          (b) %o                             (c) %x                                (d) %u Ans) c

40. Find the output of the following program
                            main()
                            {
                                int x=5, *p;
                                p=&x
                                printf("%d",++*p);
                            }
        (a) 5                                    (b) 6                                    (c) 0                                    (d) none of these

Ans ) b
41.Consider the following C code
                            main()
                            {
                                int i=3,x;
                                while(i>0)
                                {
                                    x=func(i);
                                    i--;
                                }
                                int func(int n)
                                {
                                    static sum=0;
                                    sum=sum+n;
                                    return(sum);
                                }
                            }
        The final value of x is
        (a) 6                                (b) 8                                (c) 1                                  (d) 3

43. Int *a[5] refers to
        (a) array of pointers        (b) pointer to an array        (c) pointer to a pointer          (d) none of these

Ans )

44.Which of the following statements is incorrect
        (a)                 typedef struct new
                            {
                                int n1;
                                char n2;
                            } DATA;

        (b)                typedef struct
                            {
                                int n3;
                                char *n4;
                            }ICE;

        (c)                typedef union
                            {
                                int n5;
                                float n6;
                            } UDT;

(d)                        #typedef union
                            {
                                int n7;
                                float n8;
                            } TUDAT;

==============================================================

. These programs may look simple and few might have guessed the right answer for the following.But i want to give the internal detail of working. So that you need not worry when you find this kind of programs in life. It involves very beautiful concepts like STACK, VARARG procedure, Function invoking .

main( )

{

int i = 3;

printf ("%d %d\n", i++, ++i );

}

ANS : 4 4

printf is a VARARG function, i.e printf is implemented to handle variable number of ( any number of ) arguments. Its simple template is

int printf ( char *, ... );

Here first argument should be an address ( Char * ) and it is must be there always. That means you can not write printf with less than one argument, so the minimum is one and the first one should be of an address ( Char *).

See a simple example.

main ( )

{

char name[] = "ramakrishna" ;

printf ( name ); /* it is absolutely OK */

}

After char* agrument it can take any number of arguments irrespective of number % 's in the first argument. But it has few important features that you should concentrate.

Before invoking PRINTF function, arguments are pushed on to the STACK in REVERSE ORDER ( Right to left).

So printf ("%d %d\n", i++, ++i ); has two arguments. one is i ++ and another one is ++ i . So before executing the function printf pushes ++ i onto the stack.

i.e ( ++ 3 is 4 pushed on to the stack ) then it pushes i ++ onto the stack. ( 4++ is 4 pushed onto the stack ).

stack is as below

after pushing it executes the first argument. that is " %d %d "

As soon as it find first %d it pops the stack and print an integer.

so it prints 4, after finding the second %d it again pops the stack and print another integer. This is how you will get 4 4.

************* But what happens when you have two arguments and more %'s in the first argument. IT IS WHAT THE MOST IMPORTANT *********************

IT PRINTS SOME MEANINGFUL Value . That is ,Let me discuss something about STACK. All the local variables you are going to declare in a program are always stored in STACK ( It vanishes once the context is over and it is Last In First Out (LIFO) Memory ).

While daclaring locals all the locals are stored in STACK. For the below program it pushes int i ( that is 3 onto the stack ) and printf arguments are pushed again in the same way.

That is STACK look like this.

THIRD : 4 /* i++ */

SECOND : 4 /* ++ i */

FIRST : 3 /* Local variable */

But because of statement i ++ , i value will increment the stack will be like this

THIRD : 4 /* i++ */

SECOND : 4 /* ++ i */

FIRST : 5 /* Local variable */

2.)

main( )

{

int i = 3;

printf ("%d %d %d \n", i++, ++i );

}

While printing when it find first %d it prints the top of stack. That is 4, for second %d it prints next one 4 , for the last %d even though printf don't have last argument it prints 5.

I think I CONFUSED you , but NO PROBLEM once you understand this CONCEPT, you NEED NOT SEE THIS KIND OF PROGRAMS IN YOUR LIFE AGAIN

Prints garbage value in turbo C!!!!

main( )

{

int i = 3;

int j = 10;

printf ("%d %d %d \n", i++, ++i );

}

stack will be like this

FOURTH : 4 /* ++ i */

THIRD : 4 /* i++ */

SECOND : 10 /* Local variable j = 10 */

FIRST : 3 /* Local variable i variables are always stored according to their order of declaration */

NOTE : Three %d s print 4 4 10

Four %d s print 4 4 10 3

( In some compilers it may not be answer,)

Section 1. Declarations and Initializations

1.1: How do you decide which integer type to use?

A: If you might need large values (tens of thousands), use long.

Otherwise, if space is very important, use short. Otherwise,

use int.

1.4: What should the 64-bit type on a machine that can support it?

A: C9X specifies long long.

1.7: What's the best way to declare and define global variables?

A: The best arrangement is to place each definition in some

relevant .c file, with an external declaration in a header file.

1.11: What does extern mean in a function declaration?

A: Nothing, really; the keyword extern is optional here.

1.12: What's the auto keyword good for?

A: Nothing.

1.14: I can't seem to define a linked list node which contains a

pointer to itself.

A: Structures in C can certainly contain pointers to themselves;

the discussion and example in section 6.5 of K&R make this

clear. Problems arise if an attempt is made to define (and use)

a typedef in the midst of such a declaration; avoid this.

1.21: How do I declare an array of N pointers to functions returning

pointers to functions returning pointers to characters?

A: char *(*(*a[N])())();

Using a chain of typedefs, or the cdecl program, makes these

declarations easier.

1.22: How can I declare a function that returns a pointer to a

function of its own type?

A: You can't quite do it directly. Use a cast, or wrap a struct

around the pointer and return that.

1.25: My compiler is complaining about an invalid redeclaration of a

function, but I only define it once.

A: Calling an undeclared function declares it implicitly as

returning int.

1.25b: What's the right declaration for main()?

A: See questions 11.12a to 11.15.

1.30: What am I allowed to assume about the initial values

of variables which are not explicitly initialized?

A: Uninitialized variables with "static" duration start out as 0,

as if the programmer had initialized them. Variables with

"automatic" duration, and dynamically-allocated memory, start

out containing garbage (with the exception of calloc).

1.31: Why can't I initialize a local array with a string?

A: Perhaps you have a pre-ANSI compiler.

1.31b: What's wrong with "char *p = malloc(10);" ?

A: Function calls are not allowed in initializers for global or

static variables.

1.32: What is the difference between char a[] = "string"; and

char *p = "string"; ?

A: The first declares an initialized and modifiable array; the

second declares a pointer initialized to a not-necessarily-

modifiable constant string.

1.34: How do I initialize a pointer to a function?

A: Use something like "extern int func(); int (*fp)() = func;" .

Section 2. Structures, Unions, and Enumerations

2.1: What's the difference between struct x1 { ... }; and

typedef struct { ... } x2; ?

A: The first structure is named by a tag, the second by a typedef

name.

2.2: Why doesn't "struct x { ... }; x thestruct;" work?

A: C is not C++.

2.3: Can a structure contain a pointer to itself?

A: See question 1.14.

2.4: What's the best way of implementing opaque (abstract) data types

in C?

A: One good way is to use structure pointers which point to

structure types which are not publicly defined.

2.6: I came across some code that declared a structure with the last

member an array of one element, and then did some tricky

allocation to make it act like the array had several elements.

Is this legal or portable?

A: An official interpretation has deemed that it is not strictly

conforming with the C Standard.

2.7: I heard that structures could be assigned to variables and

passed to and from functions, but K&R1 says not.

A: These operations are supported by all modern compilers.

2.8: Is there a way to compare structures automatically?

A: No.

2.10: Can I pass constant values to functions which accept structure

arguments?

A: Not yet. As of this writing, C has no way of generating

anonymous structure values.

2.11: How can I read/write structures from/to data files?

A: It is relatively straightforward to use fread and fwrite.

2.12: How can I turn off structure padding?

A: There is no standard method.

2.13: Why does sizeof report a larger size than I expect for a

structure type?

A: The alignment of arrays of structures must be preserved.

2.14: How can I determine the byte offset of a field within a

structure?

A: ANSI C defines the offsetof() macro, which should be used if

available.

2.15: How can I access structure fields by name at run time?

A: Build a table of names and offsets, using the offsetof() macro.

2.18: I have a program which works correctly, but dumps core after it

finishes. Why?

A: Check to see if a structure type declaration just before main()

is missing its trailing semicolon, causing main() to be declared

as returning a structure. See also questions 10.9 and 16.4.

2.20: Can I initialize unions?

A: The current C Standard allows an initializer for the first-named

member.

2.22: What is the difference between an enumeration and a set of

preprocessor #defines?

A: At the present time, there is little difference. The C Standard

states that enumerations are compatible with integral types.

2.24: Is there an easy way to print enumeration values symbolically?

A: No.

Section 3. Expressions

3.1: Why doesn't the code "a[i] = i++;" work?

A: The variable i is both referenced and modified in the same

expression.

3.2: Under my compiler, the code "int i = 7;

printf("%d\n", i++ * i++);" prints 49. Regardless of the order

of evaluation, shouldn't it print 56?

A: The operations implied by the postincrement and postdecrement

operators ++ and -- are performed at some time after the

operand's former values are yielded and before the end of the

expression, but not necessarily immediately after, or before

other parts of the expression are evaluated.

3.3: What should the code "int i = 3; i = i++;" do?

A: The expression is undefined.

3.3b: Here's a slick expression: "a ^= b ^= a ^= b". It swaps a and b

without using a temporary.

A: Not portably; its behavior is undefined.

3.4: Don't precedence and parentheses dictate order of evaluation?

3.3b: Here's a slick expression: "a ^= b ^= a ^= b". It swaps a and b

without using a temporary.

A: Not portably; its behavior is undefined.

3.4: Don't precedence and parentheses dictate order of evaluation?

A: Operator precedence and explicit parentheses impose only a

partial ordering on the evaluation of an expression, which does

not generally include the order of side effects.

3.5: But what about the && and || operators?

A: There is a special exception for those operators: left-to-right

evaluation is guaranteed.

3.8: What's a "sequence point"?

A: A point (at the end of a full expression, or at the ||, &&, ?:,

or comma operators, or just before a function call) at which all

side effects are guaranteed to be complete.

3.9: So given a[i] = i++; we don't know which cell of a[] gets

written to, but i does get incremented by one, right?

A: *No*. Once an expression or program becomes undefined, *all*

aspects of it become undefined.

3.12: If I'm not using the value of the expression, should I use i++

or ++i to increment a variable?

A: Since the two forms differ only in the value yielded, they are

entirely equivalent when only their side effect is needed.

3.14: Why doesn't the code "int a = 1000, b = 1000;

long int c = a * b;" work?

A: You must manually cast one of the operands to (long).

3.16: Can I use ?: on the left-hand side of an assignment expression?

A: No.

Section 4. Pointers

4.2: What's wrong with "char *p; *p = malloc(10);"?

A: The pointer you declared is p, not *p.

4.3: Does *p++ increment p, or what it points to?

A: *p++ increments p. To increment the value pointed to by p, use

(*p)++ .

4.5: I want to use a char * pointer to step over some ints. Why

doesn't "((int *)p)++;" work?

A: In C, a cast operator is a conversion operator, and by

definition it yields an rvalue, which cannot be assigned to, or

incremented with ++.

4.8: I have a function which accepts, and is supposed to initialize,

a pointer, but the pointer in the caller remains unchanged.

A: The called function probably altered only the passed copy of the

pointer.

4.9: Can I use a void ** pointer as a parameter so that a function

can accept a generic pointer by reference?

A: Not portably.

4.10: I have a function which accepts a pointer to an int. How can I

pass a constant like 5 to it?

A: You will have to declare a temporary variable.

4.11: Does C even have "pass by reference"?

A: Not really, though it can be simulated.

4.12: I've seen different methods used for calling functions via

A: The extra parentheses and explicit * are now>

Transfer interrupted!

older implementations require them.

Section 5. Null Pointers

5.1: What is this infamous null pointer, anyway?

A: For each pointer type, there is a special value -- the "null

pointer" -- which is distinguishable from all other pointer

values and which is not the address of any object or function.

5.2: How do I get a null pointer in my programs?

A: A constant 0 in a pointer context is converted into a null

pointer at compile time. A "pointer context" is an

initialization, assignment, or comparison with one side a

variable or expression of pointer type, and (in ANSI standard C)

a function argument which has a prototype in scope declaring a

certain parameter as being of pointer type. In other contexts

(function arguments without prototypes, or in the variable part

of variadic function calls) a constant 0 with an appropriate

explicit cast is required.

5.3: Is the abbreviated pointer comparison "if(p)" to test for non-

null pointers valid?

A: Yes. The construction "if(p)" works, regardless of the internal

representation of null pointers, because the compiler

essentially rewrites it as "if(p != 0)" and goes on to convert 0

into the correct null pointer.

5.4: What is NULL and how is it #defined?

A: NULL is simply a preprocessor macro, #defined as 0 (or

((void *)0)), which is used (as a stylistic convention, in

preference to unadorned 0's) to generate null pointers.

5.5: How should NULL be defined on a machine which uses a nonzero bit

pattern as the internal representation of a null pointer?

A: The same as on any other machine: as 0. (The compiler makes the

translation, upon seeing a 0, not the preprocessor; see also

question 5.4.)

5.6: If NULL were defined as "((char *)0)," wouldn't that make

function calls which pass an uncast NULL work?

A: Not in general. The complication is that there are machines

which use different internal representations for pointers to

different types of data. A cast is still required to tell the

compiler which kind of null pointer is required, since it may be

different from (char *)0.

5.9: If NULL and 0 are equivalent as null pointer constants, which

should I use?

A: Either; the distinction is entirely stylistic.

5.10: But wouldn't it be better to use NULL, in case the value of NULL

changes?

A: No. NULL is a constant zero, so a constant zero is equally

sufficient.

5.12: I use the preprocessor macro "#define Nullptr(type) (type *)0"

to help me build null pointers of the correct type.

A: This trick, though valid, does not buy much.

5.13: This is strange. NULL is guaranteed to be 0, but the null

pointer is not?

A: A "null pointer" is a language concept whose particular internal

value does not matter. A null pointer is requested in source

code with the character "0". "NULL" is a preprocessor macro,

which is always #defined as 0 (or ((void *)0)).

5.14: Why is there so much confusion surrounding null pointers?

A: The fact that null pointers are represented both in source code,

and internally to most machines, as zero invites unwarranted

assumptions. The use of a preprocessor macro (NULL) may seem to

suggest that the value could change some day, or on some weird

machine.

5.15: I'm confused. I just can't understand all this null pointer

stuff.

A: A simple rule is, "Always use `0' or `NULL' for null pointers,

and always cast them when they are used as arguments in function

calls."

5.16: Given all the confusion surrounding null pointers, wouldn't it

be easier simply to require them to be represented internally by

zeroes?

A: Such a requirement would accomplish little.

5.17: Seriously, have any actual machines really used nonzero null

pointers?

A: Machines manufactured by Prime, Honeywell-Bull, and CDC, as well

as Symbolics Lisp Machines, have done so.

5.20: What does a run-time "null pointer assignment" error mean?

A: It means that you've written, via a null pointer, to an invalid

location. (See also question 16.8.)

Section 6. Arrays and Pointers

6.1: I had the definition char a[6] in one source file, and in

another I declared extern char *a. Why didn't it work?

A: The declaration extern char *a simply does not match the actual

definition. Use extern char a[].

6.2: But I heard that char a[] was identical to char *a.

A: Not at all. Arrays are not pointers. A reference like x[3]

generates different code depending on whether x is an array or a

pointer.

6.3: So what is meant by the "equivalence of pointers and arrays" in

A: An lvalue of type array-of-T which appears in an expression

decays into a pointer to its first element; the type of the

resultant pointer is pointer-to-T. So for an array a and

pointer p, you can say "p = a;" and then p[3] and a[3] will

access the same element.

6.4: Why are array and pointer declarations interchangeable as

function formal parameters?

A: It's supposed to be a convenience.

6.7: How can an array be an lvalue, if you can't assign to it?

A: An array is not a "modifiable lvalue."

6.8: What is the real difference between arrays and pointers?

A: Arrays automatically allocate space which is fixed in size and

location; pointers are dynamic.

6.9: Someone explained to me that arrays were really just constant

pointers.

A: An array name is "constant" in that it cannot be assigned to,

but an array is *not* a pointer.

6.11: I came across some "joke" code containing the "expression"

5["abcdef"] . How can this be legal C?

A: Yes, array subscripting is commutative in C. The array

subscripting operation a[e] is defined as being identical to

*((a)+(e)).

6.12: What's the difference between array and &array?

A: The type.

6.13: How do I declare a pointer to an array?

A: Usually, you don't want to. Consider using a pointer to one of

the array's elements instead.

6.14: How can I set an array's size at run time?

A: It's straightforward to use malloc() and a pointer.

6.15: How can I declare local arrays of a size matching a passed-in

array?

A: Until recently, you couldn't; array dimensions had to be compile-

time constants. C9X will fix this.

6.16: How can I dynamically allocate a multidimensional array?

A: The traditional solution is to allocate an array of pointers,

and then initialize each pointer to a dynamically-allocated

"row." See the full list for code samples.

6.17: Can I simulate a non-0-based array with a pointer?

A: Not if the pointer points outside of the block of memory it is

intended to access.

6.18: My compiler complained when I passed a two-dimensional array to

a function expecting a pointer to a pointer.

A: The rule by which arrays decay into pointers is not applied

recursively. An array of arrays (i.e. a two-dimensional array

in C) decays into a pointer to an array, not a pointer to a

pointer.

6.19: How do I write functions which accept two-dimensional arrays

when the width is not known at compile time?

A: It's not always particularly easy.

6.20: How can I use statically- and dynamically-allocated

multidimensional arrays interchangeably when passing them to

functions?

A: There is no single perfect method, but see the full list for

some ideas.

6.21: Why doesn't sizeof properly report the size of an array which is

a parameter to a function?

A: The sizeof operator reports the size of the pointer parameter

which the function actually receives.

Section 7. Memory Allocation

7.1: Why doesn't the code "char *answer; gets(answer);" work?

A: The pointer variable answer has not been set to point to any

valid storage. The simplest way to correct this fragment is to

use a local array, instead of a pointer.

7.2: I can't get strcat() to work. I tried "char *s3 =

strcat(s1, s2);" but I got strange results.

A: Again, the main problem here is that space for the concatenated

result is not properly allocated.

7.3: But the man page for strcat() says that it takes two char *'s as

arguments. How am I supposed to know to allocate things?

A: In general, when using pointers you *always* have to consider

memory allocation, if only to make sure that the compiler is

doing it for you.

7.3b: I just tried the code "char *p; strcpy(p, "abc");" and it

worked. Why didn't it crash?

A: You got "lucky".

7.3c: How much memory does a pointer variable allocate?

A: Only enough memory to hold the pointer itself, not any memory

for the pointer to point to.

7.5a: I have a function that is supposed to return a string, but when

it returns to its caller, the returned string is garbage.

A: Make sure that the pointed-to memory is properly (i.e. not

locally) allocated.

7.5b: So what's the right way to return a string?

A: Return a pointer to a statically-allocated buffer, a buffer

passed in by the caller, or memory obtained with malloc().

7.6: Why am I getting "warning: assignment of pointer from integer

lacks a cast" for calls to malloc()?

A: Have you #included ?

7.7: Why does some code carefully cast the values returned by malloc

to the pointer type being allocated?

A: Before ANSI/ISO C, these casts were required to silence certain

warnings.

7.8: Why does so much code leave out the multiplication by

sizeof(char) when allocating strings?

A: Because sizeof(char) is, by definition, exactly 1.

7.14: I've heard that some operating systems don't actually allocate

malloc'ed memory until the program tries to use it. Is this

legal?

A: It's hard to say.

7.16: I'm allocating a large array for some numeric work, but malloc()

is acting strangely.

A: Make sure the number you're trying to pass to malloc() isn't

bigger than a size_t can hold.

7.17: I've got 8 meg of memory in my PC. Why can I only seem to

malloc 640K or so?

A: Under the segmented architecture of PC compatibles, it can be

difficult to use more than 640K with any degree of transparency.

C FUNDA

main()

{ char a= 'A';

if( (a=='Z')||( (a='L')&&( a=='A')))

a=a;

printf("%c",a);

printf(" Nothing ");

}

L Nothing

main()

{ static int a[5] = {2,4,6,8,10};

int i,b=5;

for(i=0; i< 5;i++){

f(a[i],&b);

printf("%d %d\n",a[i],b);

}

f(x,y)

int x,*y;

{

x=*(y)+=2;

}

main()

{

printf("hello");

fork();

}

2 7

4 9

6 11

8 13

10 15

main()

{

char as[] = "\\0\0";

int i = 0;

do{

switch( as[i++]){

case '\\' : printf("A");

break;

case 0 : printf("B");

break;

default : printf("C");

break;

}

while(i<3);

}

Ans: ACB

main()

{

int a;

a = (1,45,012);

printf("%d", a)

}

Ans: 10

012 octal ==10 in decimal

(, , ,) last value is taken

main()

{

int i = 10;

printf(" %d %d %d \n", ++i, i++, ++i);

}

Ans: 13 11 11

#include

main()

{

int arr[3][3] = {1,2,3,

4,5,6,

7,8,9};

int i,j;

for (j=2;j>=0;j--){

for(i=2;i>=0;i--){

printf("\n%d",*(*(arr+i)+j));

printf("\n TATATATA");

}

main()

{

int i = 5, j=10;

abc(&i,&j);

printf("%d..%d",i,j);

}

abc(int *i, int *j)

{

*i = *i + *j;

*j = *i - *j;

*i = *i - *j;

}

#define PRINT(int) printf( "int = %d ", int)

main()

{

int x=03,y=02,z=01;

PRINT (x | y & ~z);

PRINT (x & y && z);

PRINT (x ^ y & ~z);

}

main()

{

int a,b,c;

for (b=c=10;a= "Love Your INDIA \

TFy!QJu ROo TNn(ROo)SLq SLq ULo+UHs UJq TNn*RPn/QPbEWS_JSWQAIJO^NBELP\

eHBFHT}TnALVlBLOFAKFCFQHFOQIAIREETMSQGCSQOUHATFAJKSbEALGSkMCSlOASn^r\

^r\\tZvYxXyT|S~Pn SPm SOn TNn ULo0ULo#ULo-WHq!WFs XDt!"[b+++6];)

while(a-->64) putchar (++c=='Z'?c=c/9:33^b&1);

}

main()

{

unsigned int m[] = { 0x01,0x02, 0x04, 0x08,0x10, 0x20, 0x40, 0x80};

unsigned int n,i;

scanf("%d",&n);

for(i=0;i<=7;i++)

{ if (n& m[i])

printf("\nyes");

else

printf("\nno");

}

main()

{

int a,b=2,c;

int *pointer;

c = 3;

pointer = &c;

a = c/*pointer;

b = c /* assigning 3 to b*/;

printf("a = %d; b = %d", a,b);

}

main()

>int i ;

>i = 1;

> i= i+2*i++;

> printf("i is now %d",i);

> }

>#define MAX(x,y) (x) >(y)?(x):(y)

>main()

> int i=10,j=5,k=0;

> k= MAX(i++,++j);

> printf("%d..%d..%d",i,j,k);

> }

>main()

> const int i = 100;

> int *p = &i;

> *p = 200;

> printf("%d\n",i);

>void f(int n)

> int i;

> for(i =1;i<=n;i++)

> f(n-i);

> printf("done ");

>main()

>f(5);

>void test(int , int *);

>main()

>int * iptr, j, k = 2;

>iptr = &j;

>j = k;

>printf( "%d %d ", k, j);

>test(j, iptr);

>printf("%d %d\n", k, j);

>void test(int l, int *p)

>l++;

>(*p)++;

>#define INFINITELOOP while(1)

>main()

> INFINITELOOP

>printf("\nHello World");

>#include

>int myfunc(char *str)

> char *ptr =str;

> while(*ptr++);

> return ptr-str-1;

>main()

> printf("%d", myfunc("DESIS"));

>#include

>main(int sizeofargv, char *argv[])

>while(sizeofargv)

>printf("%s ",argv[--sizeofargv]);

>#include

>main()

>int x,y=1,z;

>if(x=z=y); x = 3;

>printf("%d %d %d\n",x,y,z);

>while (y<4) x+=++y;

>printf("%d %d\n",x,y);

>main()

>union {

>long l_e;

>float f_e;

>} u;

>long l_v;

>float f_v;

>l_v = u.l_e = 10;

>printf("%f ", (float)l_v);

>printf("%f ", u.f_e);

>f_v = u.f_e = 3.555;

>printf("%d ", (long)f_v);

>printf("%d ", u.l_e);

> }

>void main()

> char a[5] = "abcd";

> int b = 3;

> printf("%c\n",a[b]);

> printf("%c\n",((char *) b)[(int) a]);

>#define PRINTIFLESS(x,y) if((x) < (y)) printf("First is smaller");else

>main()

> int i = 2, k =1;

> if(i>0 && k>0) PRINTIFLESS(i,k);

> else printf("Numbers not greater than 0\n");

>main()

>int *iptr,*dptr, i;

>dptr = (int *) malloc(sizeof(i));

>iptr =&i ;

>*iptr = 10;

>free(iptr);

>*dptr = 20;

>/*dptr = iptr;*/

>free(dptr);

>printf("%d,%d,%d",*dptr,*iptr,i);

>main()

>char line[80];

>gets(line);

>puts(line);

>main()

>char c1;

>int i=0;

>c1='a';

>while(c1>='a' && c1 <='z')

>c1++;

>i++;

>printf("%d",i);

>main()

>char ch = 'A';

>while(ch <='F'){

> switch(ch){

> case 'A':case 'B':case 'C': case 'D': ch++; continue;

> case 'E': case 'F': ch++;

> }

>putchar(ch);

>#include

>main()

>FILE *fp1,*fp2;

>fp1 = fopen("one","w");

>fp2 = fopen("one","w");

>fputc('A',fp1);

>fputc('B',fp2);

>fclose(fp1);

>fclose(fp2);

>int a[50000];

>main(){

>main()

> int a = 0xff;

>if(a<<4>>12)

> printf("Right");

>else

> printf("Wrong");

>#include

>main()

> enum _tag{ left=10, right, front=100, back};

> printf("left is %d, right is %d, front is %d, back is

%d",left,right,front,back);

>#include

>main()

>char *arr = "This is to test";

>printf("\n%c %c ",*(arr), *(arr++));

>#include

>main()

>int I =-3, j=2, k = 0,m;

>m = ++I && ++j || ++k;

>printf("\n%d %d %d %d", I, j, k, m);

>int a[50000];

>main(){}

>static int i = 6;

>extern i;

>main()

>printf("%d",i);

>#include

>#define MAX 20

>main()

> FILE *fp1, *fp2;

> char *this1, *this2;

> fp1 = fopen("ip1.dat","r");

> if(fp1==NULL)printf("file open error\n");

> fp2 = fopen("ip2.dat","r");

> if(fp2==NULL)printf("file open error\n");

> if((getline(this1,fp1)!=0) && (getline(this2,fp2)!=0)){

> if(strcmp(this1,this2))

> continue;

> else { printf("lines do not match\n"); break;}

> }

>int getline(char *line, FILE *fp)

>if(fgets(line,MAX, fp) == NULL)

> return 0;

>else

> return strlen(line);

>#include

>main()

> FILE *fp;

>fp = fopen("testbuf.txt", "wt");

>fwrite("1. This is fwrite\n",1, 18, fp);

>write(fileno(fp), "2.This is write\n", 17);

>fclose(fp);

>#define PR(a) printf("a = %d\t",(int) (a));

>#define PRINT(a) PR(a); putchar('\n');

>#define FUDGE(k) k + 3.14

>main()

> int x = 2;

> PRINT( x * FUDGE(2));

>#include

>main()

>int i = 3,j;

>j = add(++i);

>printf("i = %d j = %d\n", i, j);

>add(ii)

>int ii;

>ii++;

>printf("ii = %d\n", ii);

>#define DEBUG(args) (printf("DEBUG: "), printf args)

>main()

> int n = 0,i = 0 ;

> printf("%d\n", n);

> if(n != 0) DEBUG(("n is %d\n", n));

> DEBUG(("%d",i));

>main()

> char *s2, *s1 ;

> s1* = malloc(sizeof (char) * 20);

> s1 = "Hello, ";

> s2 = "world!";

> strcat(s1, s2);

> printf("%s ", s1);

>char*s="char*s=%c%s%c;main(){printf(s,34,s,34);}";

> main(){printf(s,34,s,34);}

>main()

> char *s1 = "alpha", *s2 = "alpha";

> if(!strcmp(s1,s2)) printf("yes\n");

>#define DEBUG(args) (printf("DEBUG: "), printf args)

>main()

> int n = 10;

> if(n != 0) DEBUG(("n is %d\n", n));

>>}

>main()

>int i;

>struct

> {

> int left,y;

> }a;

>printf("%5d\n",a[i].left);

>#include

>main()

>char c1,c2,c3;

>c1 = getc(stdin);

>putc(c1,stdout);

>c2 = getche();

>putc(c2,stdout);

>c3 = getchar();

>putc(c3,stdout);

>#include

>struct test{

>int f;

>};

>struct test*

>f(struct test * (*fPtr)() )

>struct test *ptr = (struct test*) malloc(sizeof(struct test));

>return ptr;

>main()

> f(f)->f;

>main()

>print_in_reverse( "char *str" );

>void print_in_reverse( char *str )

> if( *str == '\0' )

> return;

> print_str_in_reverse(str+1);

> printf( "%c" , *str );

>#include

>/* #define sqrt(x) (( x < 0) ? sqrt(-x) : sqrt(x))

>*/

>main()

>int y;

>y = sqrt(-9);

>printf("%d",y);

>#define MAXI 100

>main(){

>int done,i,x=6;

>done=i=0;

>for(i = 0; (i< MAXI) && (x/=2)>1; i++)

>done++;

>printf("%d %d\n",i,done);

>#define MAXI 100

>main(){

>int done,i,x=6;

>done=i=0;

>while (i < MAXI && !done){

>if ((x/=2)>1){ i++; continue;}

>done++;

>printf("%d %d\n",i,done);

>main()

> struct emp

> { char name[20];

> int age;

> float sal;

> };

> struct emp e = {"Tiger"};

> printf("\n%d %f",e.age,e.sal);

>main()

>char str[] = "Taj is 2 miles away";

>int i;

>for(i=0;i<19;++i)

>if(isalpha(str[i]))printf("%c",toupper(str[i]));

>main()

>int c;

>while((c=getchar()) != 0){

>printf(" %c",c);

>#include

>f( )

> printf("I am f()");

>extern f1( );

>main()

> int i=10;

> f1(i);

>f1(int i )

> printf("the i value is %d",i);

> f();

>#include

>#define abs(x) x>0?x:-x

>#define mabs(x) (((x)>=0)?(x):-(x))

>int fabs(int);

>main()

>printf("\n%d %d",abs(10)+1,abs(-10)+1);

>printf("\n%d %d",mabs(10)+1,mabs(-10)+1);

>printf("\n%d %d\n",fabs(10)+1,fabs(-10)+1);

>int fabs(int n)

>return(n>0? n: -n);

>unsigned char

>f(unsigned n)

> static const unsigned char table[64] = {

> 0, 0, 0, 9, 0, 0, 10, 1, 0, 0, 0, 0, 0, 11, 2, 21, 7, 0, 0, 0, 0,

0, 0,

> 15, 0, 0, 12, 0, 17, 3, 22, 27, 32, 8, 0, 0, 0, 0, 0, 20, 6, 0, 0,

14,

> 0, 0, 16, 26, 31, 0, 0, 19, 5, 13, 0, 25, 30, 18, 4, 24, 29, 23,

28, 0

> };

> return table[((n & -n) * 0x1d0d73df) >> 26];

>main()

>printf("%c",f(8));

>#include

>int myfunc(char *str)

> char *ptr =str;

> while(*ptr++);

> return ptr-str-1;

>main()

> printf("length is %d", myfunc("DESIS"));

>#include

>struct _tag

> int i;

> union

> {

> int a;

> int b;

> }c;

>} a;

>main()

> a.c.a=10;

> printf("test %d\n",a.c.b);

>main()

> int a=10,b;

> b=a>=5?100:200;

> printf("%d\n",b);

>#define MAXI 100

>main(){

>int x=6,done,i;

>done=i=0;

>do

> if((x/=2)>1)

> {i++; continue;}

> else

> done++;

>}while ((i < MAXI) && !done);

>printf("%d %d\n",i,done);

>#include

>main()

>extern int i;

>i=20;

>printf("%d\n",sizeof(i));

>fun()

>printf("Yes\n");

>#define fun() printf("No\n")

>main()

> fun();

> (fun)();

>main()

> int i = 1;

> switch(i) {

> printf("\nHello, ");

> case 1: printf("One, ");

> i++;

> break;

> case 2: printf("Two");

> break;

> }

>#define DESHAWCURRENTDEBUGLEVEL 1

>void main(void)

>int i = 10 ;

>int j = 15 ;

>#ifdef DESHAWCURRENTDEBUGLEVEL

>printf("%d\n",i);

>#else

>printf("%d\n",j);

>#endif

>#define scanf "%s DE Shaw"

>main()

> printf(scanf,scanf);

> }

>main()

> char *p="abc";

> char *q="abc123";

> while(*p==*q)

> {

> printf("%c %c",*p,*q);

> p++;q++;

> }

>#define INTPTR int *

>main()

> INTPTR pi, pj;

> int i,j;

> i=10;j=20;

> pi = &j;

> pj = &j;

> j++;

> i= *pi;

> printf("%d,",i);

> j++;

> i= *pj;

> printf("%d",i);

>#include

>main()

>char strp[] = "Never ever say no";

>char *chp, c='e';

>int i,j;

>chp = strrchr(strp, c);

>i = chp-strp;

>for(j=0;j<=i;j++)printf("%c",strp[j]);

>#include

>main()

> char str[] ="abcdef";

> printf("str is %s",str);

> str = "DESIS";

> printf("str is %s",str);

>main()

> char *str ="India pvt. ltd.";

> char *str1 = "DESIS";

> printf("str is %s",str);

> printf("str is %s",str1);

> strcat(str1,str);

> printf("str is %s",str1);

>main()

> char str[] ="DESIS India pvt. ltd.";

> const char *str1= str;

> strcpy(str1,"DESHAW");

> printf("str is %s",str);

>main()

>int i=4,j=2,k=0;

>char c1='a',c2='b';

>if(k==0)printf("k is zero\n");

>else if(j==2)printf("j is 2\n");

>else if(i==4)printf("i is 4\n");

>if(c1!='a')printf("c1 is not a\n");

>else if (c2=='a')printf("c2 is b");

>else printf("Hello\n");

>#include

>main()

>int a[3] = {1,2,3};

>int i= 2;

>printf("\n %d %d\n", a[i], i[a]);

>#include

>void fun(int, int*);

>main()

>int j,i;

>int * intptr;

>printf("enter an integer\n");

>scanf("%d",&i);

>intptr = &j;

>j = i;

>printf("i and j are %d %d \n",i,j);

>fun(j,intptr);

>printf("i is:%d",i);

>printf("\n j is:%d",j);

>void fun(int k, int *iptr)

>k++;

>(*iptr)++;

>return;

>#include

>main()

> int x;

> x = printf("%d\n",x=printf("%d",890));

> printf("%d",x);

> }

>#include

>main()

>int i;

>char c;

>for (i=0;i<5;i++){

> scanf("%d",&c);

> printf("%d",i);

> }

>main()

> int x = 10,y=2,z;

> z=x/*y+y*/+y;

> printf("%d\n",z);

>main()

>int a[] = {0,1,2,3,4};

>int *p[] = {a,a+1,a+2,a+3,a+4};

>int **pp = p;

>printf("%d, %d, %d ", *pp-a, pp-p, **pp);

>pp++; pp++;;++pp;*++pp;

>printf("%d, %d, %d ", pp-p, *pp-a, **pp);

>main()

>int a[] = {0,1,2,3,4};

>int *p[] = {a,a+1,a+2,a+3,a+4};

>int **pp = p;

>printf("%d, %d, %d ", *pp-a, pp-p, **pp);

>pp++; *pp++;++pp;*++pp;

>printf("%d, %d, %d ", pp-p, *pp-a, **pp);

>main()

>char input[] = "SSSWILTECH1\1\1";

>int i, c;

>for ( i=2; (c=input[i])!='\0'; i++){

> switch(c){

> case 'a': putchar ('i'); continue;

> case '1': break;

> case 1: while (( c = input[++i]) != '\1' && c!= '\0');

> case 9: putchar('S');

> case 'E': case 'L': continue;

> default: putchar(c);continue;

> }

> putchar(' ');

> }

> putchar('\n');

>main(){

>unsigned int k = 987 , i = 0;

>char trans[10];

> do {

> trans[i++] = (k%16 > 9) ? (k%16 - 10 + 'a') : (k%16 -

'0' );

> } while(k /= 16);

> for(i=0;i<10;i++) printf("%c", trans[i]);

>main()

>unsigned int k = 987 , i = 0;

>char trans[10];

> do {

> trans[i++] = (k%16 > 9 ? k%16 - 10 + 'a' : k%16 - '0' );

> printf("%d %d\n",k,k%16);

> } while(k /= 16);

> printf("%s\n", trans);

> }

>main()

>char *pk;

>const char* p;

>const char c = 'a';

>char c1='b';

>p=&c1;

>pk = &c;

>printf("%c %c",*pk,*p);

>main()

>int i=4;

>if (i>5) printf("Hi");

>else f(i);

>f(int j)

>if (j>=4) f(j-1);

>else if(j==0)return;

>printf("Hi");

>int *NEXT(register int i)

>int *ipt;

>ipt = &i;

>ipt++;

>return ipt;

>main ()

>int j;

>printf("%d",(NEXT(j)));

>#define PRINT(int) printf("int = %d ",int)

>main()

>int x,y,z;

>x=03;y=02;z=01;

>PRINT(x^x);

>z<<=3;PRINT(x);

>y>>=3;PRINT(y);

>#define PRINT(int) printf( "int = %d ", int)

>main()

>int x=03,y=02,z=01;

>PRINT (x | y & ~z);

>PRINT (x & y && z);

>PRINT (x ^ y & ~z);

>main()

>int p;

>for(p = 1; p<=10, --p ; p=p+2)

> puts("Hello");

>#include

>int n, R;

>main()

>R = 0;

>scanf("%d",&n);

>printf("\n %d, %d",fun(n),R);

>int fun(int n)

>if (n>3) return

> R = 5;

> R = 6;

> return(1);

> }

>main()

>int a = 10, b = 5,c = 3,d = 3;

>if ((a

>else printf(" %d %d %d %d ", a, b, c, d);

>main()

>struct test

>char c;

>int i;

>char v;

>} t1;

>printf("%d %d\n",sizeof(t1), sizeof(t1.c));

>#include

>main()

>int a,b;

>scanf("%d %d", &a, &b);

>printf("%d\n", a+++b);

>printf("%d %d\n",a,b);

>float s=1944,x[5],y[5],z[5],r[5],j,h,a,b,d,e;int i=33,c,l,f=1;int

g(){return f=

>(f*6478+1)%65346;}m(){x[i]=g()-l;y[i]=(g()-l)/4;r[i]=g()>>4;}main(){char

t[1948

>]="

`MYmtw%FFlj%Jqig~%`jqig~Etsqnsj3stb",*p=t+3,*k="3tjlq9TX";l=s*20;while(i

>p[i++]='\n'+5;for(i=0;i<5;i++)z[i]=(i?z[i-1]:0)+l/3+!m();while(1){for(c=33;c

>c++){c+=!((c+1)%81);j=c/s-.5;h=c%81/40.0-1;p[c]=37;for(i=4;i+1;i--)if((b=(a=h*x

>[i]+j*y[i]+z[i])*a-(d=1+j*j+h*h)*(-r[i]*r[i]+x[i]*x[i]+y[i]*y[i]+z[i]*z[i]))>0)

>{for(e=b;e*e>b*1.01||e*e

>(i=4;i+1;z[i]-=s/2,i--)z[i]=z[i]<0?l*2+!m():z[i];while(i

>int i;

>main()

> char a[] = "Shiva";

> printf("%c\n",i[a]);

>myread(a,b)

> printf("%d %d",a,b);

>main()

> myread(2,4);

>funct(char* str)

> printf("%s\n",str);

>main()

> static int ii = 1;

> int jj = 5;

> ii+=++jj;

> funct(ii+++"Campus Interview");

>funct(str)

> printf("%s\n",str);

>main()

> funct('-'-'-'+"DEShaw");

>main()

> printf(" %d\n",'-'-'-'-'/'/'/');

> }

>static int a = 6;

>extern int a;

>main()

> printf("%d",a);

> }

>#include

>main()

>int i=6,j=4;

>printf("NO\n");

>switch(i)

>do{

>case 1: printf("yes\n");

>case 2:

>case 3:

>case 4:

>case 5:

>case 6:

> j--;

> }while (j);

> }

>#include

>main()

>auto int i = 0;

>printf("%d\n",i);

> {

> int i = 2;

> printf("%d\n",i);

> {

> i+=1;

> printf("%d\n",i);

> }

> printf("%d\n",i);

> }

>printf("%d\n",i);

>printf("%d\n",reset());

>printf("%d\n",ret10());

>printf("%d\n",reset());

>printf("%d\n",ret10());

>int reset()

>int j = 0;

>return(j);

>int ret10()

>static int i = 10;

>i+=1;

>return(i);

>#include

>main()

>struct emp1

> char *name;

> int age;

>};

>struct emp2

>char *cp;

>struct emp1 e1;

>}e2 = {"ghi",{"jkl",123}};

>struct emp1 e3 = {"rwer",2341};

>printf("\n%s %d\n",e3.name,e3.age);

>printf("\n%s %s %d\n",e2.cp,e2.e1.name,e2.e1.age);

>struct xyz{

> int xyz ;

> }

> ;

>main()

>union xyz{

> int xyz;

> }

> ;

> }

>#include

>main()

>char s[] = "Bouquets and Brickbats";

>printf("\n%c, ",*(&s[2]));

>printf("%s, ",s+5);

>printf("\n%s",s);

>printf("\n%c",*(s+2));

>#include

>struct s

> {

> char *st;

> struct s *sptr;

> };

>main()

>int i;

>struct s *p[3];

>static struct s a[]={

> {"abcd",a+1},

> {"pqrs",a+2},

> {"stuv",a}

> };

>for( i=0;i<3;i++ )p[i] = a[i].sptr;

>swap(*p,a);

>printf("%s %s %s \n",p[0]->st,(*p)->st, (*p)->sptr->st);

>swap(p1,p2)

>struct s *p1,*p2;

>char *temp;

>temp = p1->st;

>p1->st = p2->st;

>p2->st = temp;

>Swap( int *x , int *y)

>int tmp = *x ;

>*y = *x ;

>*x = tmp;

>main()

>int a = 1, b = 2;

>Swap(&a, &b);

>printf("%d %d\n", a, b);

>main()

> int i;

> scanf("%d",&i);

> switch(i) {

> printf("\nHello");

> case 1: printf("\none");

> break;

> case 2: printf("\ntwo");

> break;

> }

>#include

>main()

>int x;

>x = 3;

>f(x);

>printf("MAIN");

>f(int n)

>printf("F");

>if (n != 0)

>f(n-1);

>#include

>main()

> int ptr[] = {1,2,23,6,5,6};

> char str[] = {'a','b','c','d','e','f','g','h'};

> printf("pointer differences are %ld, %d",&ptr[3], &str[3]-&str[0]);

> }

>#include

>main()

>char a,b,c;

>scanf("%c %c %c",&a,&b,&c);

>printf("%c %c %c ", a, b, c);

>#include

>main()

> int a = 10000;

> char b='c';

> int i,j;

> /* i=printf("%d\n",a);

> j=printf("%c\n",b);*/

> printf("%d,%d",printf("%d\n",a),printf("%c\n",b));

> }

>#include

>#define PR(a) printf("%d\t",(int) (a));

>#define PRINT(a,b,c) PR(a);PR(b);PR(c);

>#define MAX(a,b) (a

>main(){

> int x = 1,y = 2;

> PRINT(MAX(x++,y),x,y);

> }

>#include

>main()

> unsigned int i=100;

>for(;i>=0;i--) printf("hello: %u\n",i);

>main()

>struct list{

>int x;

>struct ist next;

>}head;

>struct ist{

>int x;

>int y;

>};

>head.x = 100;

>head.next.x=10;

>printf("%d %d", head.x,head.next.x);

>main()

>typedef union

>struct

>char c1,c2;

>} s;

>long j;

>float x;

>} U;

>U example;

>example.s.c1 = 'a';

>example.s.c2 = 'b';

>example.j = 5;

>printf("%c %c %d", example.s.c1, example.s.c2, example.j);

>main()

> {

> struct s1

> { char *str;

> struct s1 *ptr;

> };

> static struct s1 arr[] = { {"Hyderabad",arr+1},

> {"Bangalore",arr+2},

> {"Delhi",arr}

> };

> struct s1 *p[3];

> int i;

> for(i=0;i<=2;i++)

> p[i] = arr[i].ptr;

> printf("%s\n",(*p)->str);

> printf("%s\n",(++*p)->str);

> printf("%s\n",((*p)++)->str);

> }

>main()

> {struct s1

> { char *str;

> struct s1 *ptr;

> };

> static struct s1 arr[] = { {"Hyderabad",arr+1},

> {"Bangalore",arr+2},

> {"Delhi",arr}

> };

> struct s1 *p[3];

> int i;

> for(i=0;i<=2;i++) p[i] = arr[i].ptr;

>printf("%s ",(*p)->str);

> printf("%s ",(++*p)->str);

>printf("%s ",((*p)++)->str);

> }

>main()

>char input[] = "SSSWILTECH1\1\1";

>int i, c;

>for ( i=2; (c=input[i])!='\0'; i++){

> switch(c){

> case 'a': putchar ('i'); continue;

> case '1': break;

> case 1: while (( c = input[++i]) != '\1' && c!= '\0');

> case 9: putchar('S');

> case 'E': case 'L': continue;

> default: putchar(c);continue;

> }

> putchar(' ');

> }

> putchar('\n');

>main()

>int i, n, m, b, x[25];

>int f1(int, int, int j[25]);

>for(i=0;i<25;i++) x[i] = i;

>i=0; m = 24;

>b=f1(i, m, x);

>printf("res %d\n",b);

>int f1( int p, int q, int a[25])

>int m1,m2;

>if (q==0)

>return(a[p]);

>else

>m1 = f1 (p, q/2, a);

>m2 = f1(p+q/2+1,q/2,a);

>if(m1

>return (m2);

>else

>return(m1);

>main()

>int a[3][4] ={1,2,3,4,5,6,7,8,9,10,11,12} ;

>int i,j,k=99 ;

>for(i=0;i<3;i++)

>for(j=0;j<4;j++)

>if(a[i][j] < k) k = a[i][j];

>printf("%d", k);

>main()

>char *p = "hello world!";

>p[0] = 'H';

>printf("%s",p);

Bottom of Form 1

************************ CITICORP ***********************************

1]. The following variable is available in file1.c

static int average_float;

all the functions in the file1.c can access the variable

[2]. extern int x;

Check the answer

[3]. Another Problem with

# define TRUE 0

some code

while(TRUE)

{

some code

}

This won't go into the loop as TRUE is defined as 0

[4]. A question in structures where the memebers are dd,mm,yy.

mm:dd:yy

09:07:97

[5]. Another structure question

1 Rajiv System Analyst

[6]. INFILE.DAT is copied to OUTFILE.DAT

[7]. A question with argc and argv .

Input will be

c:\TEMP.EXE Ramco Systems India

-----------------------------------------------------------------------

main()

{

int x=10,y=15;

x=x++;

y=++y;

printf("%d %d\n",x,y);

}

----------------------------------------------------------------------

int x;

main()

{

int x=0;

{

int x=10;

x++;

change_value(x);

x++;

Modify_value();

printf("First output: %d\n",x);

}

x++;

change_value(x);

printf("Second Output : %d\n",x);

Modify_value();

printf("Third Output : %d\n",x);

}

Modify_value()

{

return (x+=10);

}

change_value()

{

return(x+=1);

}

----------------------------------------------------------------------------

main()

{

int x=20,y=35;

x = y++ + x++;

y = ++y + ++x;

printf("%d %d\n",x,y);

}

-----------------------------------------------------------------------

main()

{

char *p1="Name";

char *p2;

p2=(char *)malloc(20);

while(*p2++=*p1++);

printf("%s\n",p2);

}

----------------------------------------------------------------------

main()

{

int x=5;

printf("%d %d %d\n",x,x<<2,x>>2);

}

--------------------------------------------------------------------

#define swap1(a,b) a=a+b;b=a-b;a=a-b;

main()

{

int x=5,y=10;

swap1(x,y);

printf("%d %d\n",x,y);

swap2(x,y);

printf("%d %d\n",x,y);

}

int swap2(int a,int b)

{

int temp;

temp=a;

b=a;

a=temp;

return;

}

----------------------------------------------------------------------

main()

{

char *ptr = "Ramco Systems";

(*ptr)++;

printf("%s\n",ptr);

ptr++;

printf("%s\n",ptr);

}

---------------------------------------------------------------------

#include

main()

{

char s1[]="Ramco";

char s2[]="Systems";

s1=s2;

printf("%s",s1);

}

-----------------------------------------------------------------

#include

main()

{

char *p1;

char *p2;

p1=(char *) malloc(25);

p2=(char *) malloc(25);

strcpy(p1,"Ramco");

strcpy(p2,"Systems");

strcat(p1,p2);

printf("%s",p1);

}

C QUESTIONS:WHAT IS THE OUT PUT FOR FOLLOWING PROGRAMMS

1)main()

{

char a[2];

*a[0]=7;

*a[1]=5;

printf("%d",&a[1]-a)

ANS:

ans may be 1.(illegal initialization)

#include

main(){

char a[]="hellow";

char *b="hellow";

char c[5]="hellow";

printf("%s %s %s ",a,b,c);

printf(" ",sizeof(a),sizeof(b),sizeof(c));

}

(ans is hellow,hellow,hellow

6,2,5 )

#include

main()

float value=10.00;

printf("%g %0.2g %0.4g %f",value,value,value,value)

}

(ans is 10,10,10,10.000000)

#include

void function1;

int i-value=100;

main()

{

i-value=50;

function1;

printf("i-value in the function=",i-value);

printf("i-value after the function=",i-value);

}

printf("i-value at the end of main=",i-value);

functioni()

i-value=25;

THIS IS ROUGH IDEA OF THE PROGRAM

ANS ARE

1)i-value in the function=25;

2)i-value after the function=50;

3)i-value at the end of the main=100;

main()

{

funct(int n);

{

switch(n)

case1:

m=2;

break;

case2:

m=5;

break;

case3:

m=7;

break;

default:

m=0;

}

THIS IS ROUGH IDEA:

(ANS:Out put is m=0)

I am sending mainly c paper and some questions.Rao also will send somethig.There are 15 c q's all are discriptive.

1)fallacy

f()

{

int a;

void c;f2(&c,&a);

2)a=0;

b=(a=0)?2:3;

a) What will be the value of b? why

b) If in 1st stmt a=0 is replaced by -1, b=?

c) If in second stmt a=0 is replaced by -1, b=?

3)char *a[2]

int const *p;

int *const p;

struct new { int a;int b; *var[5] (struct new)

4)f()

{

int a=2;

f1(a++);

}

f1(int c)

{

printf("%d", c);

}

c=?

5)f1()

{

f(3);}

f(int t)

{

switch(t);

{

case 2: c=3;

case 3: c=4;

case 4: c=5;

case 5: c=6;

default: c=0;}

value of c?

6)Fallacy

int *f1()

{

int a=5;

return &a;

}

f()

int *b=f1()

int c=*b;

}

7)a)Function returning an int pointer

b)Function ptr returning an int ptr

c)Function ptr returning an array of integers

d)array of function ptr returning an array of integers

(See Scham series book)

8)fallacy

int a;

short b;

b=a;

9)Define function ?Explain about arguments?

10)C passes By value or By reference?

11)Post processed code for

abc=1;

b=abc1; (1 or 2 blank lines are given)

strcpy(s,"abc");

z=abc;

12)difference between my-strcpy and strcpy ?check

13)f()

{

int *b;

*b=2;

}

14)Function which gives a pointer to a binary trees const an integer value

at each code, return function of all the nodes in binary tree.(Study)Check

15)Calling refernce draw the diagram of function stack illustrating the

variables in the -----then were pushed on the stack at the point when

function f2 has been introduced

type def struct

{ double x,double y} point;

main( int argc, char *arg[3])

{double a;

int b,c;

f1(a,b);}

f1(double x, int y)

{

point p;

stack int n;

f2(p,x,y)}

f2(point p, double angle)

{ int i,j,k,int max)

}

________________________________________________________

1. main(){

int mat[3][3] = { 1,2,3,4,5,6,7,8,9 };

int i, j;

for ( i = 2; i >= 0 ; i-- )

for ( j = 2; j >= 0 ; j-- )

printf("%d", *(*mat+j)+i);

}

a). 9 8 7 6 5 4 3 2 1 b). 1 2 3 4 5 6 7 8 9 c). 9 6 3 8 5 2 7 4 1 d). None of the above

2. main() {

printf("Hello\n");

fork();

printf("Hi\n");

}

You are supposed to justify your answer in interview.

3. int count = 10, *temp, sum = 0;

temp = &count;

*temp = 20;

temp = ∑

*temp = count;

printf("%d %d %d\n", count *temp, sum);

(a). 10 20 0 (b). 20 20 20 (c). 20 20 10 (d). None of the above

4. main() {

enm tag = { left = 10, right, front = 100, back };

printf("%d %d %d %d", left, right, front, back);

}

(a). compile time error b). 10 11 100 101 (c). 10 11 12 13 (d). 1 2 3 4

5. What is the value of i if you pass value of i to

the following function?

foo(const int &j) {

j++;

}

(a). Compile error (b). 10 (c). prints addition of I (d). 11

6. You are reading from inpur file to buffer. Buffer terminates with NULL, the char you need is ch.Write a C program.

7. Write a program to add 10 between 100 and total is not initialezed.

8. while ( (*p++ = *q++) != 0 ) { }

What does the above line of C code do ?

Same as strcpy() in C.

9. main() {

int n = 3;

f(n);

printf("MAIN");

}

void f(int n) {

printf("F");

if ( n != 0 )

f(n-1);

}

What is the output of the above code? Ans. FFFF

10. main() {

char s[] = "Never ever look it" , *ch, c = 'e' ;

int i, j;

chr = strcmp ( s, c);

i = chr - s;

for ( i = 0; i < j; i++ )

printf("%d", s[i] );

}

What is the o/p of the program ?

(a). Never eve (b). Never ev (c). error (d). None of the above

11. main() {

union u {

struct s {

char c1, c2;

};

long x;

float y;

};

u example ;

example.s.c1 = 'a' ;

example.s.c2 = 'b' ;

example.x = 5;

printf("%c %c %d", example.s.c1, example.s.c2, example.x);

}

(a). a b 5 b). 0 0 5 (c). garbage garbage 5 (Correct) (d). error

12 main() {

int i, j, k = 0;

char c1 = 'a', c2 = 'b';

if ( k == 0 )

printf("K is zero");

else

-----

if ( c1 != 'a' )

printf("c2 == b");

else if ( c2 == 'a' )

printf("c1 == a");

else

printf("Hello");

}

(a). K is zero c1 == a

(b). " c2 == b

(c). " Hello (Correct) (d). error

13. If you don't declare a function and you are calling in main(), Does C support this or not ?

14. When a function returns where form the memory allocated? Ans. Stack

15. void (*((int, void (*)())));

Ans. (c)

Python/Networking/Security/Virtualization Fundamentals

Pages

Monday, February 27, 2012

C Q&A (contd)

C FUNDA