Having trouble loading from a text file C++ - c++

Question

I'm having trouble loading from a text file to a value. I want it to load from the text file, but the number remains unchanged.
Data.txt
7
7
Line 1 of the file is Health, what I'm trying to load.
Player.h
#ifndef PLAYER_H
#define PLAYER_H
class Player
{
public:
int Health;
int MaxHealth;
Player() { this->Health = 9; this->MaxHealth = 9; }
};
#endif // PLAYER_H
and main.cpp
#include <iostream>
#include "Player.h"
#include <fstream>
using namespace std;
void save_to_file(string filename, Player P)
{
ofstream f( filename.c_str() );
f << P.Health << endl;
f << P.MaxHealth << endl;
}
bool load_from_file(string filename, Player P)
{
ifstream f( filename.c_str() );
f >> P.Health;
f >> P.MaxHealth;
return f.good();
}
int main()
{
Player P;
load_from_file("Data.txt", P);
cout << P.Health << endl;
return 0;
}
Thanks! I just learned C++ so I'm a little confused. I'm running Codeblocks and 'Data.txt' is in the 'bin' folder.
EDIT :
Changed main.
bool load_from_file(string filename, Player& P)
{
ifstream f( filename.c_str() );
f >> P.Health;
f >> P.MaxHealth;
if(f.good()){
cout << "Sucess!" << endl;
} else {
cout << "Failure" << endl;
}
return f.good();
}

Answer 1

Not sure what you're doing wrong if you followed πάντα ῥεῖ's advice, but this works:
#include <iostream>
#include <fstream>
using namespace std;
class Player {
public:
int Health, MaxHealth;
};
void save_to_file(string filename, const Player& P)
{
ofstream f( filename.c_str() );
f << P.Health << endl;
f << P.MaxHealth << endl;
}
bool load_from_file(string filename, Player& P) {
ifstream f( filename.c_str() );
f >> P.Health;
f >> P.MaxHealth;
if(f.good()){
cout << "Success!" << endl;
}
else {
cout << "Failure" << endl;
}
return f.good();
}
int main() {
Player P;
load_from_file("Data.txt", P);
cout << P.Health << endl;
return 0;
}

Answer 2

Change your function signature to take the parameter by reference:
bool load_from_file(string filename, Player& P) {
// ^
As is, your function only modifies a copy of the Player parameter, and the result isn't seen in main().