In C programming language, constants are essential because they give us a mechanism to store unchanging values that hold true throughout the course of the program. These numbers may be used for several things, such as creating mathematical constants or giving variables set values.
In C programming, the constants are the read-only values that doesn't change as the program runs. Constants can be of several types, such as integers, floating-point numbers, characters, and strings. When a constant has a value, it cannot be changed, unlike variables.
They may be utilized in various operations and computations and serve as the program's representation of fixed values.
Ways to define constant in C
There are mainly two ways to define the constant in C programming.
- const keyword
- #define preprocessor
Here, we will discuss these different ways one by one.
- Using const keyword
In C programming, the const keyword is mainly utilized to define a constant in a program. When we want to define a constant using the const keyword, the constant value cannot be changed during the program.
- Using #define preprocessor
In C programming, we can use the #define preprocessor directive to define constants without specifying a data type. During the compilation stage, it helps to simply replace all constant instances with its value. It’s commonly used for defining constant values, such as mathematical constants, configuration values, and flags. This process helps to make our code more readable and maintainable.
Types of Constant in C
There are different types of Constants in C. Some of them are as follows:
• Integer Constants
• Floating-Point Constants
• Character Constants
• String Constants
• Enumeration Constants
• Double Precision Floating-Point Constant
Here, we will discuss all these constants one by one,
1.) Integer Constants
In C programming, integer constants represent whole numbers without any fractional or decimal components. These integer constants can be positive or negative and can be written without any quotes
2.) Real or Floating-Point Constant
In C programming, a real or floating-point constant represents the fractional component or exponentiation of a number. It can be expressed with a decimal point, the letter "E", or the symbol "e" in exponential or decimal notation.
3.)String Constant
In C programming, a series of characters wrapped in double quotes is represented by a string constant. It is a character array that ends with the null character \0.
4.)Enumeration Constants
In C programming, enumeration constants are the user-defined constants that are used to represent a set of integer values. We can use the enum keyword to define the enumeration constants. It enables us to create a set of named integer constants, which helps to improve code readability and organization.
5.) Enumeration Constants
In C programming, enumeration constants are the user-defined constants that are used to represent a set of integer values. We can use the enum keyword to define the enumeration constants. It enables us to create a set of named integer constants, which helps to improve code readability and organization.
6.) Double Precision Floating-Point Constant
In C programming, the double-precision floating-point constant is similar to a floating-point constant but it provides higher precision than the float. These constants are stored using the double data type, which occupies more memory (8 bytes) and offers more than 15-17 digits of precision.
