Explain union, C/C++ Programming

Assignment Help:

Unions

A union is also like a structure, except that only single variable in the union is stored in the allocated memory at a time. It is a collection of mutually exclusive variables, which means all of its member variables share the similar physical storage and only one variable is explained at a time. The size of the union is equal to the largest member variables. A union is defined as follows :

                union tag

                 {

                                type memvar1;

                                type memvar2;

                                type memvar3;

                                :

                                :

                 };

 

A union variable of this data type can be declared as follows,

Union tag variable_name;

e.g.

                union utag

                 {

                                int num;

                                char ch;

                 };

                union tag filed;

The above union will have two bytes of storage allocated to it. The variable num can be accessed as field.sum and ch is accessed as field.ch. At any time, only one of these two variables,  can be referred to. Any change made to single variable affects another.

 


Related Discussions:- Explain union

Program to design list in c, Program to design list in c: Write a prog...

Program to design list in c: Write a program in c to insert the values in list void main() { int i=0; char a[20]; clrscr(); printf("Enter the line\n");

Stone game, how to write a c program for stone game

how to write a c program for stone game

Arguments passing mechanism, Arguments Passing Mechanism C++ supports th...

Arguments Passing Mechanism C++ supports the following argument passing mechanisms: i).  Pass by value: A copy of the arguments value is made and passed to the called functio

Luminous jevel, Ask queByteland county is very famous for luminous jewels. ...

Ask queByteland county is very famous for luminous jewels. Luminous jewels are used in making beautiful necklaces. A necklace consists of various luminous jewels of particular colo

When should i use references, A: Use references when you can use, and use p...

A: Use references when you can use, and use pointers when you have to. References are generally preferred over pointers whenever you don't require "reseating". Usually this mean

Write a program to design a leet speak translator, The program will consist...

The program will consist of two text fields, two buttons, and a counter label.  One text field will be input, where the user types the plain text.  The second text field will be ou

C program to design text styles, Program to design text styles: Write ...

Program to design text styles: Write a C program to design different text style char *fname[] = { "DEFAULT font",                                   "TRIPLEX font",

What are user defined data types, Q: What are User Defined data types? ...

Q: What are User Defined data types? C supports an extraordinary feature known as "type definition" that permits users to define an identifier that would represent an existing

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd