Output of C programs | Set 34

Ques 1. Assume that the size of an integer is 4 bytes and size of character is 1 byte. What will be the output of following program? C

#include <stdio.h>
union test {
    int x;
    char arr[8];
    int y;
} u;
int main()
{
    printf("%u", sizeof(u));
    return 0;
}

options : A)12 B)16 C)8 D)4

Answer - C

Explanation : In union data type, the memory required to store a union variable is the memory required for the largest element of an union. Ques 2. What will be the output of following program? C

#include <stdio.h>
int main()
{
    int n;
    for (n = 9; n != 0; n--)
        printf("%d", n--);
}

options : A)9 7 5 3 1 B)9 8 7 6 5 4 3 2 1 C)Infinite loop D)9 7 5 3

Answer - C

Explanation : The loop will run infinite time because n will never be equal to 0. Ques 3. What will be the output of following program? C

#include <stdio.h>
int main()
{
    int x = 1;
    if (x = 0)
        printf("Geeks");
    else
        printf("Geeksforgeeks");
}

Options : A)Geeks B)runtime error C)Geeksforgeeks D)compile time error

Answer  - C

Explanation : Here we are assigning(=) and not comparing(==) x with 0 which is not true so the else part will execute and print Geeksforgeeks. Ques 4.What will be output of following c code? C

#include <stdio.h>
int main()
{
    int i = 2, j = 2;
    while (i + 1 ? --i : j++)
        printf("%d", i);
    return 0;
}

Options : A)1 B)2 C)0 D)No output

Answer : A

Explanation: Consider the while loop condition:

i + 1 ? -- i : ++j

In first iteration: i + 1 = 3 (True), So ternary operator will return

 -–i i.e. 1

In C, 1 means true so while condition is true. Hence printf statement will print 1 In second iteration: i + 1 = 2 (True), So ternary operator will return

-–i i.e. 0

In C, zero means false so while condition is false. Hence program control will come out of the while loop. Ques 5. Assume that the size of an integer is 4 bytes and size of character is 1 byte. What will be the output of following program? C

#include <stdio.h>
struct test {
    int x;
    char arr[8];
    int y;
} u;
int main()
{
    printf("%u", sizeof(u));
    return 0;
}

options : A)12 B)16 C)8 D)4

Answer - B

Explanation : In structure data type, The amount of memory required to store a structure variable is the sum of memory size of all members.