Preprocessor Directive: "#include"
Preprocessor Directives Commands that are given to the preprocessor are called Preprocessor Directives. All preprocessor commands / directives begin with pound sign (also known as hash symbol - #). Since they are not C/C++ commands, therefore, never put semicolon at the end of a preprocessor directive. These commands are given to the C/C++ preprocessor to change the source code. But the changes last only as long as the compile takes place. Once the code is complied and converted into program, the original source code is restored. Its important to remember that the preprocessor does not in any way compile your program or look at the actual C/C++ statements. Preprocessor directives are the special non-C/C++ commands, that make changes to your source code before the compiler start its work. First the preprocessor is activated to execute the preprocessor directives/commands, then the compilation process takes. So by Preprocessor we mean, the changes are made t...