If you want to use same memory location for two or more members, union is the best for that . Unions are similar to the structure. Union variables are created in same manner as structure variables.
Read moreWhat is the difference between a struct and a union?
A union is like a struct in that it generally has several fields, all of which are public by default. Unlike a struct, however, only one of the fields is used at any given time. In other words, it is a structure that allows the same storage space to be used to store values of different data types at different times.
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