What does union mean in c language

Union is a data type in C language that can be used to save memory by allowing different types of data to be stored in the same memory location. It is used by declaring a structure containing members of different types, which share the same memory location, so that only one member's data can be stored at a time.

union in C

UNION is a C keyword that allows you to Store different types of data.

Function:

• Save memory space because it only allocates memory space once to store different types of data.
• Allows access to different types of data in the same memory location without the need to convert data types.

Syntax:

<code class="c">union union_name {
    data_type1 member1;
    data_type2 member2;
    ...
};</code>

Among them:

• ##union_name is the name of the union.
• data_type1, data_type2, etc. are members of union, and they can have different data types.

Usage:

1. Declare a union: Use the above syntax to declare a union.
2. Access members: Use the dot operator (.) to access members of the union, for example: union_name.member1.
3. Storing data: Members in a Union share the same memory location, so you can only store data for one member at a time. When you store a new value, it overwrites the previously stored value.

Example:

<code class="c">union my_union {
    int integer;
    float floating_point;
    char character;
};

my_union my_data;

my_data.integer = 10;
printf("Integer value: %d\n", my_data.integer);

my_data.floating_point = 3.14;
printf("Floating-point value: %f\n", my_data.floating_point);</code>

In the above example,

my_union is a union containing integer, floating point and character members. We first store an integer and then a float. Since the members of a union share the same memory location, the value of a floating point number will overwrite the value of an integer.

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