C Constants is the most fundamental and essential part of the C programming language. Constants are the fixed values that are used in a program, and its value remains the same during the entire execution of the program.
Rules of constants
- Constants are also called literals.
- Constants can be any of the data types.
- It is considered a best practice to define constants using only upper-case names.
const data_type variable_name;
const data_type *variable_name;
Declaration of Constant
const type constant_name;
Example of Constant
const int SIDE = 10;
area = SIDE*SIDE;
printf("The area is %d",area);
The area is 100
Constants can be of following types.
- integer constant.
- floating constant.
- character constant.
- string literal.
The following table shows the constants and its data types with Example
|constant type||data type(Example)|
|integer constant||int (53, 762, -478 etc ) unsigned int (5000u, 1000U etc) long int, long long int (483,647 2,147,483,680)|
|floating constant||float (10.456789) doule (600.123456789)|
|character constant||char (Example: ‘A’, ‘B’, ‘C’)|
|string literal||char (Example: “ABCD”, “Hai”)|