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

Genetic disease, Many human diseases could be controlled by the knowledge o...

Many human diseases could be controlled by the knowledge of the gene’s structure and pattern. The human gene could be represented by four nucleotides. Each nucleotide is represente

Described the isa and hasa class relationships. , Described the ISA and HAS...

Described the ISA and HASA class relationships. How would you apply each in a class design? A: A specialized class "is" specialization of another class and, thus, has the ISA re

Explain logical operators, Logical Operators We say any expression that...

Logical Operators We say any expression that evaluates to zero is a FALSE logic condition and that evaluating to non-zero value is a TRUE condition. Logical operators are usefu

Char, how many bytes required to char

how many bytes required to char

Arrays, how to declare multi dimensional array

how to declare multi dimensional array

We want network-social app, We are seeking a talented developer/team with g...

We are seeking a talented developer/team with great experience in programming apps for both Android and iOS. Our project needs great skills and experience in making good functional

Minimum Shelf , At a shop of marbles, packs of marbles are prepared. Packet...

At a shop of marbles, packs of marbles are prepared. Packets are named A, B, C, D, E …….. All packets are kept in a VERTICAL SHELF in random order. Any numbers

Computes the amount of postage count even or odd, (a) Write a procedure (co...

(a) Write a procedure (count-even n) that counts the number of even digits in the decimal representation of the number n. For example, (count-even 234) should return 2. (b) Writ

Maths, .Write a program to find the area under the curve y = f(x) between x...

.Write a program to find the area under the curve y = f(x) between x = a and x = b, integrate y = f(x) between the limits of a and b.

Database, write a c++ program to update employee records

write a c++ program to update employee records

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