Union in C Language - Quiz

Q: Comment on the following union declaration?


    #include <stdio.h>
    union temp
    {
        int a;
        float b;
        char c;
    };

union temp s = {1,2.5,'A'}; //REF LINE Which member of the union will be active after REF LINE?

A. a
B. b
C. c
D. Such declaration are illegal

Correct Option: A
Remarks:

Explanation: a

Q: What would be the size of the following union declaration?


    #include <stdio.h>
    union uTemp
    {
        double a;
        int b[10];
        char c;
    }u;

(Assuming size of double = 8, size of int = 4, size of char = 1)

A. 4
B. 8
C. 40
D. 80

Correct Option: C
Remarks:

Explanation: 40

Q: Members of a union are accessed as________________

A. union-name.member
B. union-pointer->member
C. both union-name.member & union-pointer->member
D. none of the mentioned

Correct Option: C
Remarks:

Explanation: both union-name.member & union-pointer->member

Q: 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

Correct Option: C
Remarks:

Explanation: 4

Q: What is the output of this C code?

    #include "stdio.h"
    union stu
    {
        int ival;
        float fval;
    };
    void main()
    {
        union stu r;
        r.ival = 5;
        printf("%d", r.ival);
    }

A. 9
B. Compile time error
C. 16
D. 5

Correct Option: D
Remarks:

Explanation: 5

Q: What will be the output of the program?

#include"stdio.h"

int main()
{
    union a
    {
        int i;
        char ch[2];
    };
    union a u;
    u.ch[0]=3;
    u.ch[1]=2;
    printf("%d, %d, %d\n", u.ch[0], u.ch[1], u.i);
    return 0;
}

A. 3, 2, 515
B. 515, 2, 3
C. 3, 2, 5
D. 515, 515, 4

Correct Option: A
Remarks:

Explanation: Option A

Q: What will be the output of the program?

#include"stdio.h"

int main()
{
    union var
    {
        int a, b;
    };
    union var v;
    v.a=10;
    v.b=20;
    printf("%d\n", v.a);
    return 0;
}

A. 10
B. 20
C. 30

Correct Option: B
Remarks:

Explanation: 20

Q: 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

Correct Option: A
Remarks:

Explanation: 103 DotNet

Q: What is the output of this C code?


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

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

Correct Option: D
Remarks:

Explanation: sizeof(int)

Q: Which of the following share a similarity in syntax?
1. Union, 2. Structure, 3. Arrays and 4. Pointers

A. 3 and 4
B. 1 and 2
C. 1 and 3
D. 1, 3 and 4

Correct Option: B
Remarks:

Explanation: 1 and 2

Union in C Language - Quiz

Comment on the following union declaration?
union temp s = {1,2.5,'A'}; //REF LINE Which member of the union will be active after REF LINE?

What would be the size of the following union declaration?
(Assuming size of double = 8, size of int = 4, size of char = 1)

Members of a union are accessed as________________

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)); }

What is the output of this C code?
#include "stdio.h" union stu { int ival; float fval; }; void main() { union stu r; r.ival = 5; printf("%d", r.ival); }

What will be the output of the program?
#include"stdio.h" int main() { union a { int i; char ch[2]; }; union a u; u.ch[0]=3; u.ch[1]=2; printf("%d, %d, %d\n", u.ch[0], u.ch[1], u.i); return 0; }

What will be the output of the program?
#include"stdio.h" int main() { union var { int a, b; }; union var v; v.a=10; v.b=20; printf("%d\n", v.a); return 0; }

What will be the output of the program?

What is the output of this C code?

Which of the following share a similarity in syntax?
1. Union, 2. Structure, 3. Arrays and 4. Pointers

Union in C Language - Quiz

Comment on the following union declaration? #include <stdio.h> union temp { int a; float b; char c; }; union temp s = {1,2.5,'A'}; //REF LINE Which member of the union will be active after REF LINE?

What would be the size of the following union declaration? #include <stdio.h> union uTemp { double a; int b[10]; char c; }u; (Assuming size of double = 8, size of int = 4, size of char = 1)

Members of a union are accessed as________________

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)); }

What is the output of this C code? #include "stdio.h" union stu { int ival; float fval; }; void main() { union stu r; r.ival = 5; printf("%d", r.ival); }

What will be the output of the program? #include"stdio.h" int main() { union a { int i; char ch[2]; }; union a u; u.ch[0]=3; u.ch[1]=2; printf("%d, %d, %d\n", u.ch[0], u.ch[1], u.i); return 0; }

What will be the output of the program? #include"stdio.h" int main() { union var { int a, b; }; union var v; v.a=10; v.b=20; printf("%d\n", v.a); return 0; }

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; }

What is the output of this C code? #include <stdio.h> union { int x; char y; }p; int main() { p.x = 10; printf("%d\n", sizeof(p)); }

Which of the following share a similarity in syntax? 1. Union, 2. Structure, 3. Arrays and 4. Pointers

Comment on the following union declaration?
union temp s = {1,2.5,'A'}; //REF LINE Which member of the union will be active after REF LINE?

What would be the size of the following union declaration?
(Assuming size of double = 8, size of int = 4, size of char = 1)

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)); }

What is the output of this C code?
#include "stdio.h" union stu { int ival; float fval; }; void main() { union stu r; r.ival = 5; printf("%d", r.ival); }

What will be the output of the program?
#include"stdio.h" int main() { union a { int i; char ch[2]; }; union a u; u.ch[0]=3; u.ch[1]=2; printf("%d, %d, %d\n", u.ch[0], u.ch[1], u.i); return 0; }

What will be the output of the program?
#include"stdio.h" int main() { union var { int a, b; }; union var v; v.a=10; v.b=20; printf("%d\n", v.a); return 0; }

What will be the output of the program?

What is the output of this C code?

Which of the following share a similarity in syntax?
1. Union, 2. Structure, 3. Arrays and 4. Pointers