C++ Primer Plus, Fourth Edition

Summary

Functions are the C++ programming modules. To use a function, you need to provide a definition and a prototype, and you have to use a function call. The function definition is the code that implements what the function does. The function prototype describes the function interface: how many and what kinds of values to pass to the function and what sort of return type, if any, to get from it. The function call causes the program to pass the function arguments to the function and to transfer program execution to the function code.

By default, C++ functions pass arguments by value. This means that the formal parameters in the function definition are new variables that are initialized to the values provided by the function call. Thus, C++ ...