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

Implementing functions, An employee’s total weekly pay equals the hourly wa...

An employee’s total weekly pay equals the hourly wage multiplied by the total number of regular hours plus any overtime pay. Overtime pay equals the total overtime hours multiplied

Need payment gateway integration expert, Need Payment Gateway Integration E...

Need Payment Gateway Integration Expert Project Description: I am seeking for expert payment gateway integration. You must have done or have experience with integrating me

What is buddy systems, Buddy systems : A method of handling the storage man...

Buddy systems : A method of handling the storage management problem is kept individual free lists for blocks of dissimilar sizes. Every list having free blocks of only one particul

Multiple constructor, Constructor public class ListNode {    //...

Constructor public class ListNode {    // package access members; List can access these directly private E data; // data for this node privateListNode nextNode; /

Program create a user defined data structure - c++ program, Create a user-d...

Create a user-defined data structure (struct) called Node that represents a node within a linked list where the "data" stored in each node is a pointer to a Car object.    a) Wr

Recursive function, Write a recursive function recursiveMin that takes an i...

Write a recursive function recursiveMin that takes an integer array, a starting subscript and an ending subscript as arguments, and returns the smallest element in the array. The f

What happens while a derived-class object is developed, What happens while ...

What happens while a derived-class object is developed & destroyed? A: Space is allocated (on the heap or the stack) for the full object (i.e. adequate space to store the data m

Help me for an programming contest .., Pebble Merchant Problem Description...

Pebble Merchant Problem Description There is a pebble merchant. He sells the pebbles, that are used for shining the floor. His main duty is to take the length of the room’s sides

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