In structure each member get separate space in memory. … In union, the total memory space allocated is equal to the member with largest size. All other members share the same memory space . This is the biggest difference between structure and union.
Read moreWhat is the difference between struct and union in C++?
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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