C++ :: Subtracting Value From 2 Integers In 2 Classes

I have 2 integers, both in 2 seperate classes in 2 seperate files. I have main.cpp, test_01.h, Test_01.cpp, Player.h and Player.cpp. I ahve a function which takes an integer (a) as a parameter (from Test_01.h and Test_01.cpp). a sets another integer (attackPower) from the same class equal to a. The integer (health) in the other class (Player.h and Player.cpp), is then equal to health -= attackPower. But instead of giving me the right answer 75 (health = 100 and a is set to 25 when i call the function) it gives me the answer.

main.cpp

#include <iostream>
#include "Test_01.h"
#include "Player.h"
using namespace std;
int main() {
Player p;
Test_01 t;

[Code] ....