Constants are immutable.

A constant is a quantity that will not be modified when a program is running. In other words, although constants serve hardware, software and programming languages, they are not introduced because of hardware, software and programming languages.

Constants are divided into different types, such as 25, 0 and -8 are integer constants, 6.8 and -7.89 are real constants, and' a' and' b' are character constants. Constants can usually be judged from their literal forms. This constant is called literal constant or direct constant.

Extended data;

In some advanced programming languages except' C/C++','constant' can be called' the quantity that never changes in the process of information change' and can be some fixed information that does not change with time; Characters (or strings) that can also be expressed as numerical values are usually used to identify, measure and compare the differences between them.

But in' C/c++ language,' constant' is not very accurate if it is described by' constant in operation', even in actual use, which is a wrong concept.

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