Union in C Language - Quiz

What is the similarity between a structure, union and enumeration?
  • A All of them let you define new values
  • B All of them let you define new data types
  • C All of them let you define new pointers
  • D All of them let you define new structures

What value will be printed for data.c? 
#include 
#include 
void main()
{
union Data{
	int i;
	unsigned char c;
}data;

data.c = 'C';
data.i = 89;
printf("%c\n", data.c);

}

  • A C
  • B Y
  • C G
  • D C89

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;
}

  • A Error: Invalid structure assignment
  • B DRAVID
  • C Dravid
  • D No output

What will be the output of the program in 16-bit platform (under DOS)? 

#include<stdio.h>

int main()
{
    struct node
    {
        int data;
        struct node *link;
    };
    struct node *p, *q;
    p = (struct node *) malloc(sizeof(struct node));
    q = (struct node *) malloc(sizeof(struct node));
    printf("%d, %d\n", sizeof(p), sizeof(q));
    return 0;
}

  • A 2, 2
  • B 8, 8
  • C 5, 5
  • D 4, 4

What is the output of this C code(size of int and float is 4)? 
    #include "stdio.h"
    union
    {
        int ival;
        float fval;
    } u;
    void main()
    {
        printf("%d", sizeof(u));
    }

  • A 16
  • B 8
  • C 4
  • D 32

What is the output of this C code? 

    #include <stdio.h>
    union
    {
        int x;
        char y;
    }p;
    int main()
    {
        p.y = 60;
        printf("%d\n", sizeof(p));
    }

  • A Compile time error
  • B sizeof(int) + sizeof(char)
  • C Depends on the compiler
  • D sizeof(char)

What is the output of this C code? 

    #include <stdio.h>
    union utemp
    {
        int a;
        double b;
        char c;
    }u;
    int main()
    {
        u.c = 'A';
        u.a = 1;
        printf("%d", sizeof(u));
    }
The output will be: (Assuming size of char = 1, int = 4, double = 8)
  • A 1
  • B 4
  • C 8
  • D 13

What will be the output of the program? 

#include<stdio.h>

    struct course
    {
        int courseno;
        char coursename[25];
    };
int main()
{
    struct course c[] = { {102, "Java"}, 
                          {103, "PHP"}, 
                          {104, "DotNet"}     };

    printf("%d ", c[1].courseno);
    printf("%s\n", (*(c+2)).coursename);
    return 0;
}

  • A 103 DotNet
  • B 102 Java
  • C 103 PHP
  • D 104 DotNet

What is the output of this C code? 

    #include <stdio.h>
    union p
    {
        int x;
        float y;
    };
    int main()
    {
        union p p, b;
        p.x = 10;
        printf("%f\n", p.y);
    }

  • A Compile time error
  • B Implementation dependent
  • C 10.000000
  • D 0.000000

What will be the output of the program? 

#include<stdio.h>

int main()
{
    enum status {pass, fail, absent};
    enum status stud1, stud2, stud3;
    stud1 = pass;
    stud2 = absent;
    stud3 = fail;
    printf("%d %d %d\n", stud1, stud2, stud3);
    return 0;
}

  • A 0, 1, 2
  • B 1, 2, 3
  • C 0, 2, 1
  • D 1, 3, 2