Unable to change values in a function

Question

I\'m starting with developing, sorry about this newbie question.

I need to create a function that swap values between 2 vars.

I have wrote this code, but no chan

Answer 1

You need to understand that by default, C++ use a call-by-value calling convention.

When you call swap_values, its stack frame receives a copy of the values passed to it as parameters. Thus, the parameters int x, int y are completely independent of the caller, and the variables int a, b.

Fortunately for you, C++ also support call-by-reference (see wikipedia, or a good programming language design textbook on that), which essentially means that the variables in your function are bound to (or, an alias of) the variables in the caller (this is a gross simplification).

The syntax for call-by-reference is:

void swap_values( int &x, int &y ){
    // do your swap here
}