C Language quiz questions

What function should be used to free the memory allocated by calloc() ?

1. dealloc();

2. malloc(variable_name, 0)

3. free();

4. memalloc(variable_name, 0)

Point out the error in the program.

#include<stdio.h>
#include<stdlib.h>
int fun(const union employee *e);
union employee
{
    char name[15];
    int age;
    float salary;
};
const union employee e1;
int main()
{
    strcpy(e1.name, "A");
    fun(&e1);
    printf("%s %d %f", e1.name, e1.age, e1.salary);
    return 0;
}
int fun(const union employee *e)
{
    strcpy((*e).name, "B");
    return 0;
}

1. Error: RValue required

2. Error: cannot convert parameter 1 from 'const char[15]' to 'char *'

3. Error: LValue required in strcpy

4. No error

What will be the output of the program?

#include<stdio.h>
int get();
int main()
{
    const int x = get();
    printf("%d", x);
    return 0;
}
int get()
{
    return 20;
}

1. Garbage value

2. Error

3. 20

4. 0

Does there exist any way to make the command-line arguments available to other functions without passing them as arguments to the function?

1. Yes

2. No

Which of the following statements correct about the below program?

#include<stdio.h>
int main()
{
    union a
    {
        int i;
        char ch[2];
    };
    union a u1 = {512};
    union a u2 = {0, 2};
    return 0;
}

1. 1, 2

2. 2, 3

3. 1, 2, 3

4. 1, 3, 4

What will be the output of the program (Turbo C in 16 bit platform DOS) ?

#include<stdio.h>
#include<string.h>
int main()
{
    char *str1 = "India";
    char *str2 = "BIX";
    char *str3;
    str3 = strcat(str1, str2);
    printf("%s %s\n", str3, str1);
    return 0;
}

1. IndiaBIX India

2. IndiaBIX IndiaBIX

3. India India

4. Error

Is there any difference int the following declarations?
int fun(int arr[]);
int fun(int arr[2]);

1. Yes

2. No

What will be the output of the program ?

#include<stdio.h>
int main()
{
    float arr[] = {12.4, 2.3, 4.5, 6.7};
    printf("%d\n", sizeof(arr)/sizeof(arr[0]));
    return 0;
}

1. 5

2. 4

3. 6

4. 7

Point out the error in the program

#include<stdio.h>
int main()
{
    int i;
    #if A
        printf("Enter any number:");
        scanf("%d", &i);
    #elif B
        printf("The number is odd");
    return 0;
}

1. Error: unexpected end of file because there is no matching #endif

2. The number is odd

3. Garbage values

4. None of above

If a function contains two return statements successively, the compiler will generate warnings. Yes/No ?

1. Yes

2. No

What will be the output of the program?

#include<stdio.h>
int main()
{
    float d=2.25;
    printf("%e,", d);
    printf("%f,", d);
    printf("%g,", d);
    printf("%lf", d);
    return 0;
}

1. 2.2, 2.50, 2.50, 2.5

2. 2.2e, 2.25f, 2.00, 2.25

3. 2.250000e+000, 2.250000, 2.25, 2.250000

4. Error

What will be the output of the program?

#include<stdio.h>
#include<math.h>
int main()
{
    float n=1.54;
    printf("%f, %f\n", ceil(n), floor(n));
    return 0;
}

1. 2.000000, 1.000000

2. 1.500000, 1.500000

3. 1.550000, 2.000000

4. 1.000000, 2.000000

Which of the following is the correct usage of conditional operators used in C?

1. a>b ? c=30 : c=40;

2. a>b ? c=30;

3. max = a>b ? a>c?a:c:b>c?b:c

4. return (a>b)?(a:b)

Point out the correct statements are correct about the program below?

#include<stdio.h>
int main()
{
    char ch;
    while(x=0;x<=255;x++)
        printf("ASCII value of %d character %c\n", x, x);
    return 0;
}

1. The code generates an infinite loop

2. The code prints all ASCII values and its characters

3. Error: x undeclared identifier

4. Error: while statement missing

Point out the error in the following program.

#include<stdio.h>
int main()
{
    char str[] = "IndiaBIX";
    printf("%.#s %2s", str, str);
    return 0;
}

1. Error: in Array declaration

2. Error: printf statement

3. Error: unspecified character in printf

4. No error

Point out the error in the following program.

#include<stdio.h>
#include<string.h>
int main()
{
    char str1[] = "Learn through IndiaBIX\0.com",  str2[120];
    char *p;
    p = (char*) memccpy(str2, str1, 'i', strlen(str1));
    *p = '\0';
    printf("%s", str2);
    return 0;
}

1. Error: in memccpy statement

2. Error: invalid pointer conversion

3. Error: invalid variable declaration

4. No error and prints "Learn through Indi"

What do the following declaration signify?

char *arr[10];

1. arr is a array of 10 character pointers.

2. arr is a array of function pointer.

3. arr is a array of characters.

4. arr is a pointer to array of characters.

Point out the correct statement will let you access the elements of the array using 'p' in the following program?

#include<stdio.h>
#include<stdlib.h>
int main()
{
    int i, j;
    int(*p)[3];
    p = (int(*)[3])malloc(3*sizeof(*p));
    return 0;
}

1. for(i=0; i<3; i++)
   {
       for(j=0; j<3; j++)
           printf("%d", p[i+j]);
   }

2. for(i=0; i<3; i++)
       printf("%d", p[i]);

3. for(i=0; i<3; i++)
   {
       for(j=0; j<3; j++)
           printf("%d", p[i][j]);
   }

4. for(j=0; j<3; j++)
       printf("%d", p[i][j]);

What will be the output of the program?

#include<stdio.h>
int main()
{
    const c = -11;
    const int d = 34;
    printf("%d, %d\n", c, d);
    return 0;
}

1. Error

2. -11, 34

3. 11, 34

4. None of these

Which of the following statements are correct about the program?

#include<stdio.h>
char *fun(unsigned int num, int base);
int main()
{
    char *s;
    s=fun(128, 2);
    s=fun(128, 16);
    printf("%s\n",s);
    return 0;
}
char *fun(unsigned int num, int base)
{
    static char buff[33];
    char *ptr = &buff[sizeof(buff)-1];
    *ptr = '\0';
    do
    {
        *--ptr = "0123456789abcdef"[num %base];
        num /=base;
    }while(num!=0);
    return ptr;
}

1. It converts a number to a given base.

2. It converts a number to its equivalent binary.

3. It converts a number to its equivalent hexadecimal.

4. It converts a number to its equivalent octal.