What is union and structure 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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How does a union struct work?

A struct is a block of memory that stores several data objects , where those objects don’t overlap. A union is a block of memory that stores several data objects, but has only storage for the largest of these, and thus can only store one of the data objects at any one time.

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