C PROGRAMMING QUESTIONS AND ANSWER contin..

(10) What will be output if you will compile and

execute the following c code?

#include<stdio.h>

#include <string.h>

int main(){

printf("%d %d",sizeof("string"),strlen("string"));

return 0;

}

(a) 6 6

(b) 7 7

(c) 6 7

(d) 7 6

(e) None of these

Answer: (d)

Explanation:
Sizeof operator returns the size of string including

null character while strlen function returns length of

a string excluding null character.

(11) What will be output if you will compile and

execute the following c code?

#include<stdio.h>

int main(){

static main;

int x;

x=call(main);

printf("%d ",x);

return 0;

}

int call(int address){

address++;

return address;

}

(a) 0

(b) 1

(c) Garbage value

(d) Compiler error

(e) None of these

Answer: (b)
Explanation:

As we know main is not keyword of c but is special type

of function. Word main can be name variable in the main

and other functions.
(12) What will be output if you will compile and

execute the following c code?

#include<stdio.h>

int main(){

int a,b;

a=1,3,15;

b=(2,4,6);

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

return 0;

}

(a) 3

(b) 21

(c) 17

(d) 7

(e) Compiler error

Answer: (d)

Explanation:
In c comma behaves as separator as well as operator.

a=1, 3, 15;

b= (2, 4, 6);

In the above two statements comma is  working as

operator. Comma enjoys least precedence and associative

is left to right.

Assigning the priority of each operator in the first

statement:

Hence 1 will assign to a.

Assigning the priority of each operator in the second

statement:


(13)  What will be output if you will compile and

execute the following c code?

#include<stdio.h>

int extern x;

int main()

printf("%d",x);

x=2;

return 0;

}

int x=23;

(a) 0

(b) 2

(c) 23

(d) Compiler error

(e) None of these

Answer: (c)

Explanation:

extern variables can search the declaration of variable

anywhere in the program.
(14) What will be output if you will compile and

execute the following c code?

#include<stdio.h>

int main(){

int i=0;

if(i==0){

i=((5,(i=3)),i=1);

printf("%d",i);

}

else

printf("equal");

}

(a) 5

(b) 3

(c) 1

(d) equal

(e) None of above

Answer: (c)

(15) What will be output if you will compile and

execute the following c code?

int main(){

int a=25;
printf("%o %x",a,a);

return 0;

}

(a) 25 25

(b) 025 0x25
(c) 12 42

(d) 31 19

(e) None of these

Answer: (d)

Explanation:

%o is used to print the number in octal number format.

%x is used to print the number in hexadecimal number

format.

Note: In c octal number starts with 0 and hexadecimal

number starts with 0x.

(16) What will be  output if you will compile and

execute the following c code?

#include<stdio.h>

#define message "union is\

power of c"

int main(){

printf("%s",message);

return 0;

}

(a) union is power of c

(b) union ispower of c
(c) union is

Power of c

(d) Compiler error

(e) None of these

Answer: (b)

Explanation:
If you want to write macro constant in new line the end

with the character \.

(17) What will be output if you will compile and

execute the following c code?

#include<stdio.h>

#define call(x) #x

int main(){

printf("%s",call(c/c++));

return 0;

}

(a)c

(b)c++

(c)#c/c++

(d)c/c++

(e)Compiler error

Answer: (d)

Explanation:

# is string operator. It converts the macro function

call argument in the string. First see the intermediate

file:

test.c 1:
test.c 2: void main(){

test.c 3: printf("%s","c/c++");

test.c 4: return 0;

test.c 4: }

test.c 5:
It is clear macro call is replaced by its argument in

the string format.

(18) What will be output if you will compile and

execute the following c code?

#include<stdio.h>

int main(){

if(printf("cquestionbank"))

else

return 0;

}

(a) I know c

(b) I know c++

(c) cquestionbankI know c

(d) cquestionbankI know c++

(e) Compiler error

Answer: (c)

Explanation:

printf("I know c");

printf("I know c++");
Return type of printf function is integer which returns

number of character it prints including blank spaces.

So printf function inside if condition will return 13.

In if condition any non- zero number means true so else

part will not execute.

(19) What will be output if you  will compile and

execute the following c code?

#include<stdio.h>
int main(){

int i=10;

static int x=i;

if(x==i)

else if(x>i)

else

return 0;

}

(a) Equal

(b) Greater than

(c) Less than

(d) Compiler error

(e) None of above

Answer: (d)

Explanation:

Static variables are load time entity while auto

variables are run time entity. We cannot initialize any

load time variable by the run time variable.

In this example i is run time variable while x is load

time variable.

printf("Equal");

printf("Greater than");

printf("Less than");

(20) What will be output if you will compile and

execute the following c code?

#include<stdio.h>

int main(){
 printf("%s",__DATE__);

return 0;

}

(a) Current system date

(b) Current system date with time

(c) null

(d) Compiler error

(e) None of these

Answer: (a)

Explanation:

__DATE__ is global identifier which returns current

system date.

(21) What will be output if you will compile and

execute the following c code?

#include<stdio.h>

void start();

void end();

#pragma startup start

#pragma exit end

int static i;
int main(){

printf("\nmain function: %d",++i);

return 0;

}
void start(){

printf("\nstart function: %d",++i);

}

void end(){

printf("\nend function: %d",++i);

}

(a)

main function: 2

start function: 1

end function:3

(b)

start function: 1

main function: 2

end function:3

(c)

main function: 2

end function:3

start function: 1

(d) Compiler error

(e) None of these

Answer: (b)

Explanation:

Every c program start with main function and terminate

with null statement. But #pragma startup can call

function just before main function and #pragma exit