C Language quiz questions

Can we specify a variable filed width in a scanf() format string?

1. Yes

2. No

The '.' operator can be used access structure elements using a structure variable.

1. True

2. False

Point out the error in the program?

#include<stdio.h>
#include<string.h>
void modify(struct emp*);
struct emp
{
    char name[20];
    int age;
};
int main()
{
    struct emp e = {"Sanjay", 35};
    modify(&e);
    printf("%s %d", e.name, e.age);
    return 0;
}
void modify(struct emp *p)
{
     p ->age=p->age+2;
}

1. Error: in structure

2. Error: in prototype declaration unknown struct emp

3. No error

4. None of above

Point out the error in the program?

#include<stdio.h>
int main()
{
    struct a
    {
        float category:5;
        char scheme:4;
    };
    printf("size=%d", sizeof(struct a));
    return 0;
}

1. Error: invalid structure member in printf

2. Error in this float category:5; statement

3. No error

4. None of above

What will be the output of the program in Turbo C (under DOS)?

#include<stdio.h>
int main()
{
    struct emp
    {
        char *n;
        int age;
    };
    struct emp e1 = {"Dravid", 23};
    struct emp e2 = e1;
    strupr(e2.n);
    printf("%s\n", e1.n);
    return 0;
}

1. Error: Invalid structure assignment

2. DRAVID

3. Dravid

4. No output

What will be the output of the program ?

#include<stdio.h>
#include<string.h>
int main()
{
    char str[] = "India\0\BIX\0";
    printf("%s\n", str);
    return 0;
}

1. BIX

2. India

3. India BIX

4. India\0BIX

Which of the statements is correct about the program?

#include<stdio.h>
int main()
{
    int arr[3][3] = {1, 2, 3, 4};
    printf("%d\n", *(*(*(arr))));
    return 0;
}

1. Output: Garbage value

2. Output: 1

3. Output: 3

4. Error: Invalid indirection

What will be the output of the program ?

#include<stdio.h>
int main()
{
    void *vp;
    char ch=74, *cp="JACK";
    int j=65;
    vp=&ch;
    printf("%c", *(char*)vp);
    vp=&j;
    printf("%c", *(int*)vp);
    vp=cp;
    printf("%s", (char*)vp+2);
    return 0;
}

1. JCK

2. J65K

3. JAK

4. JACK

What will be the output of the program ?

#include<stdio.h>
int main()
{
    int x=30, *y, *z;
    y=&x; /* Assume address of x is 500 and integer is 4 byte size */
    z=y;
    *y++=*z++;
    x++;
    printf("x=%d, y=%d, z=%d\n", x, y, z);
    return 0;
}

1. x=31, y=502, z=502

2. x=31, y=500, z=500

3. x=31, y=498, z=498

4. x=31, y=504, z=504

How many bytes are occupied by near, far and huge pointers (DOS)?

1. near=2 far=4 huge=4

2. near=4 far=8 huge=8

3. near=2 far=4 huge=8

4. near=4 far=4 huge=8

It is necessary that a header files should have a .h extension?

1. Yes

2. No

In a function two return statements should never occur.

1. Yes

2. No

What will be the output of the program?

#include<stdio.h>
int main()
{
    int i=-3, j=2, k=0, m;
    m = ++i && ++j && ++k;
    printf("%d, %d, %d, %d\n", i, j, k, m);
    return 0;
}

1. -2, 3, 1, 1

2. 2, 3, 1, 2

3. 1, 2, 3, 1

4. 3, 3, 1, 2

The modulus operator cannot be used with a long double.

1. True

2. False

What will be the output of the program?

#include<stdio.h>
#include<stdlib.h>
int main()
{
    char *i = "55.555";
    int result1 = 10;
    float result2 = 11.111;
    result1 = result1+atoi(i);
    result2 = result2+atof(i);
    printf("%d, %f", result1, result2);
    return 0;
}

1. 55, 55.555

2. 66, 66.666600

3. 65, 66.666000

4. 55, 55

What will be the output of the program (in Turbo C under DOS)?

#include<stdio.h>
int main()
{
    char huge *near *far *ptr1;
    char near *far *huge *ptr2;
    char far *huge *near *ptr3;
    printf("%d, %d, %d\n", sizeof(ptr1), sizeof(ptr2), sizeof(ptr3));
    return 0;
}

1. 4, 4, 8

2. 2, 4, 4

3. 4, 4, 2

4. 2, 4, 8

What do the following declaration signify?

void (*cmp)();

1. cmp is a pointer to an void function type.

2. cmp is a void type pointer function.

3. cmp is a function that return a void pointer.

4. cmp is a pointer to a function which returns void .

It is necessary to call the macro va_end if va_start is called in the function.

1. Yes

2. No

Can I increase the size of dynamically allocated array?

1. Yes

2. No

What will be the output of the program?

#include<stdio.h>
int fun(int **ptr);
int main()
{
    int i=10;
    const int *ptr = &i;
    fun(&ptr);
    return 0;
}
int fun(int **ptr)
{
    int j = 223;
    int *temp = &j;
    printf("Before changing ptr = %5x\n", *ptr);
    const *ptr = temp;
    printf("After changing ptr = %5x\n", *ptr);
    return 0;
}

1. Address of i
   Address of j

2. 10
   223

3. Error: cannot convert parameter 1 from 'const int **' to 'int **'

4. Garbage value