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

Explain in brief about the one-definition rule, Explain one-definition rule...

Explain one-definition rule (ODR). According to one-definition rule, C++ constructs should be identically defined in each compilation unit they are used in. As per ODR, two

C program for function of count the interest , C Program for FUNCTION OF CO...

C Program for FUNCTION OF COUNT THE INTEREST float si(float,float,float); void main() {           float p=0,r=0,n=0,k=0;           clrscr();           printf("E

Assignment, can you tell me what is c#

can you tell me what is c#

Write the program of function templates, Consider the following example: ...

Consider the following example: int max(int x, int y)                  {                                 return ( x > y) ? x : y ;                  }   float max

Area under curve, Write a program to find the area under the curve y = f(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.

Explain polymorphism, Polymorphism C++ supports this idea - that differ...

Polymorphism C++ supports this idea - that different objects do "the right thing "- by function polymorphism and class polymorphism. Poly means many, while morph means form.

Explain the bit fields portable or not, Explain the  bit fields portable o...

Explain the  bit fields portable or not? - No, Bit fields aren't portable. - As Bit fields can't span machine words and number of bits in a machine word is different on diff

#padovan string, program that counts the number of occurrences of the strin...

program that counts the number of occurrences of the string in the n-th padovan string p(n)

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