What is a pre processer?

Answer 1

C/C++ Preprocessors

As the name suggests Preprocessors are programs that process our source code before compilation. There are a number of steps involved between writing a program and executing a program in C / C++. Let us have a look at these steps before we actually start learning about Preprocessors.

You can see the intermediate steps in the above diagram. The source code written by programmers is stored in the file program.c.
Preprocessor programs provide preprocessors directives which tell the compiler to preprocess the source code before compiling. All of these preprocessor directives begin with a ‘#’ (hash) symbol. The ‘#’ symbol indicates that, whatever
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