For While Objectives



1. What is the output of this C code?

    #include <stdio.h>
    void main()
    {
        char *str = "";
        do
        {
            printf("hello");
        } while (str);
    }
a) Nothing
b) Run time error
c) Varies
d) Hello is printed infinite times
View Answer

Answer:d

2. What is the output of this C code?

    #include <stdio.h>
    void main()
    {
        int i = 0;
        while (i < 10)
        {
            i++;
            printf("hi\n");
        }
        while (i < 8)
{
         i++;
}
        printf("hello\n");
    }
a) Hi is printed 8 times, hello 7 times and then hi 2 times
b) Hi is printed 10 times, hello 1 times
c) Hi is printed once, hello 7 times
d) Hi is printed once, hello 7 times and then hi 2 times
View Answer

Answer:b

3. Example of iteration in C.

a) for
b) while
c) do-while
d) All of the mentioned

View Answer


Answer:d

4. Number of times while loop condition is tested is, i is initialized to 0 in both case.
    
while (i < n)
         i++;
    -------------
    do
         i++;
    while (i <= n);
a) n, n
b) n, n+1
c) n+1, n
d) n+1, n+1
View Answer

Answer:d

5. What is the output of this C code?

    #include <stdio.h>
    int main()
    {
        int i = 0;
        while (i = 0)
{
   printf("True\n");
}
        printf("False\n");
    }

a) True (infinite time)
b) True (1 time) False
c) False
d) Compiler dependent



View Answer

Answer:c

6. What is the output of this C code?

    #include <stdio.h>
    int main()
    {
        int i = 0, j = 0;
        while (i < 5 , j < 10)
        {
            i++;
            j++;
        }
        printf("%d, %d\n", i, j);
    }

a) 5, 5
b) 5, 10
c) 10, 10
d) Syntax error


View Answer

Answer:c

7. Which loop is most suitable to first perform the operation and then test the condition?

a) for loop
b) while loop
c) do-while loop
d) None of the mentioned


8.What is the output of this C code?

    #include <stdio.h>
    void main()
    {
        double k = 0;
        for (k = 0.0; k < 3.0; k++)
{

}
        printf("%lf", k);
    }
a) 2.000000
b) 4.000000
c) 3.000000
d) Run time error


View Answer

Answer:c


9. What is the output of this C code?

    #include <stdio.h>
    void main()
    {
        int k;
        for (k = -3; k < -5; k++)
{
             printf("Hello");
}
 printf("xyz");
    }
a) Hello
b) Infinite hello
c) Run time error
d) Nothing

ans :d

10. What is the output of this C code?

    #include <stdio.h>
    int main()
    {
        int i = 0;
        for (  ;   ; )
{
            printf("In for loop\n");
}
        printf("After loop\n");
    }
a) Compile time error
b) Infinite loop
c) After loop
d) Undefined behaviour

ans:c



11. What is the output of this C code?

    #include <stdio.h>
    int main()
    {
        int i = 0;
        for (i++; i == 1; i = 2)
            printf("In for loop ");
            printf("After loop\n");
    }
a) In for loop After loop
b) After loop
c) Compile time error
d) Undefined behaviour

ans:a

12. What is the output of this C code?

    #include <stdio.h>
    int main()
    {
        int i = 0;
        for (foo(); i == 1; i = 2)
            printf("In for loop\n");
            printf("After loop\n");
    }
    int foo()
    {
        return 1;
    }
a) After loop
b) In for loop after loop
c) Compile time error
d) Infinite loop


ans: a

13. What is the output of this C code?

    #include <stdio.h>
    int main()
    {
        int *p = NULL;
        for (foo(); p; p = 0)
            printf("In for loop\n");
            printf("After loop\n");
    }
a) In for loop after loop
b) Compile time error
c) Infinite loop
d) Depends on the value of NULL

ans:b

14. What is the output of this C code?

    #include <stdio.h>
    int main()
    {
        for (int i = 0;i < 1; i++)
            printf("In for loop\n");
    }
a) Compile time error
b) In for loop
c) Depends on the standard compiler implements
d) Depends on the compiler

ans : c



15. What is the output of this C code?

    #include <stdio.h>
    void main()
    {
        int k = 0;
        for (k < 3; k++)
        printf("Hello");
    }
a) Compile time error
b) Hello is printed thrice
c) Nothing
d) Varies

Ans:a


16. What is the output of this C code?

    #include <stdio.h>
    void main()
    {
        int i = 5, k;
        if (i == 0)
            goto label;
            label: printf("%d", i);
            printf("Hey");
    }
a) 5
b) Hey
c) 5 Hey
d) Nothing


Ans:c

17. What is the output of this C code?

    #include <stdio.h>
    int main()
    {
        printf("%d ", 1);
        goto l1;
        printf("%d ", 2);
        l1:goto l2;
        printf("%d ", 3);
        l2:printf("%d ", 4);
   }
a) 1 4
b) Compile time error
c) 1 2 4
d) 1 3 4


Ans:a

18. What is the output of this C code?

    #include <stdio.h>
    int main()
    {
        printf("%d ", 1);
        l1:l2:
        printf("%d ", 2);
        printf("%d\n", 3);
    }
a) Compile time error
b) 1 2 3
c) 1 2
d) 1 3

Ans:b

19. What is the output of this C code?

    #include <stdio.h>
    int main()
    {
        int i = 0, j = 0;
        while (i < 2)
        {
            l1: i++;
            while (j < 3)
            {
                printf("loop\n");
                goto l1;
            }
        }
   }
a) loop loop
b) Compile time error
c) loop loop loop loop
d) Infinite loop

Ans:d

20. What is the output of this C code?

    #include <stdio.h>
    int main()
    {
        while ()
            printf("In while loop ");
        printf("After loop\n");
    }
a) In while loop after loop
b) After loop
c) Compile time error
d) Infinite loop

Ans:c