16. Create functions and macros for the same or almost identical code

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Some people say that the best programmer is a program that prefers to be "lazy", which makes no sense.

If some programs have similar or identical code snippets, put them in a function. If this code is not much and will be frequently used, you should write it into a macro to avoid the overhead of function calls.

Do not make the same code or code with similar functions exist in multiple places. Otherwise, if the function changes, you need to modify several places. This will cause great trouble for maintenance, to achieve "one-to-one modification", we still need to form functions or macros.