The value of the variables aren't changing in a simple text RPG game using C++

Question

I'm trying to create a very simple turn-based text RPG game. The code compiles and runs but the attack and heal functions don't seem to change the values of the variables. I'm pretty sure it's a problem related to inheritance but I'm not sure.

#include <iostream>
#include <cstdlib>
#include <string>

using namespace std;

struct Stats {
       int hp;
       int def;
       int atk;
       int skl;
};

class Character {
      public:
             Character();
             virtual void getHit(int) = 0;
             int attack(int);
             void defend();
             virtual int getHP() = 0;

      protected:
              Stats m_Stats;
};

Character::Character() {
   m_Stats.hp = 0;
   m_Stats.def = 0;
   m_Stats.atk = 0;
   m_Stats.skl = 0;
}

int Character::attack(int def) 
{
    return (m_Stats.atk - def);
}


class Player : public Character {
      public:
             Player();
             void getHit(int);
             void healSelf();
             void fireBall();
             int getAtk();
             int getHP();
};

Player::Player()
{
     m_Stats.hp = 100;
     m_Stats.atk = 30;
     m_Stats.def = 10;
     m_Stats.skl = 10;     
}

int Player::getHP()
{
    return m_Stats.hp;
}

int Player::getAtk()
{ return m_Stats.atk; }

void Player::getHit(int atk)
{
   m_Stats.atk += m_Stats.def - atk;     
 }

void Player::healSelf()
{
     m_Stats.hp += m_Stats.skl;
     if(m_Stats.hp > 100)
        m_Stats.hp = 100;
}


class Enemy : public Character {
      public:
             Enemy();
             void getHit(int);
             void chooseAction();
             void rage();
             int choose();
             void defend();
             void resetAtk();
             int getAtk();
             int getHP();
};

Enemy::Enemy()
{
     m_Stats.hp = 150;
     m_Stats.atk = 40;
     m_Stats.def = 5;
     m_Stats.skl = 5;
}

int Enemy::getHP()
{
    return m_Stats.hp;
}

int Enemy::getAtk()
{
     return m_Stats.atk;
}

void Enemy::resetAtk()
{
     m_Stats.atk = 40;
}

int Enemy::choose()
{
     srand(time(0));
     int c = rand() % 3;
     if(c == 0)
        cout << "Enemy chooses to attack!\n";
     else if(c == 1)
        cout << "Enemy is raging!\n";
     else if(c == 2)
        cout << "Enemy chooses to defend!\n";
     return c;
}

void Enemy::rage()
{
     m_Stats.atk += 3;
 }

void Enemy::getHit(int atk)
{
   m_Stats.atk += m_Stats.def - atk;   
   m_Stats.def = 5;  
}

void Enemy::defend()
{
     m_Stats.def += 2;
}


int main()
{
    Player p;
    Enemy e;
    bool done = false; int choice, move;
    cout << "The enemy faces you!\n";
    while(!done)
    {cout << "1) Attack  2) Heal Self. ";
     cin >> choice;
     if(choice == 1)
      {  e.getHit(p.getAtk());}
     else if(choice == 2)
        {p.healSelf(); }

     cout << "Your HP: " << p.getHP() << "\n";
     cout << "Enemy HP: " << e.getHP() << "\n";

     choice = e.choose();
     if(choice == 1)
         {p.getHit(e.getAtk());
         e.resetAtk();
         }
     else if(choice == 2)
         e.rage();
     else if(choice == 3)
         e.defend();

     cout << "Your HP: " << p.getHP() << "\n";
     cout << "Enemy HP: " << e.getHP() << "\n";


     if(p.getHP() == 0 || e.getHP() == 0)
         done = true;
     }

     if(p.getHP() > e.getHP())
         cout << "You won!" << endl;
     else
         cout << "You lost!" << endl;


    system("PAUSE");
    return 0;
}

sample output

The enemy faces you!
1) Attack  2) Heal Self. 1
Your HP: 100
Enemy HP: 150
Enemy chooses to defend!
Your HP: 100
Enemy HP: 150
1) Attack  2) Heal Self: 2
Your HP: 100
Enemy HP: 150

Yeah, the output is not pretty but I'm putting off clearing up output after the code is solid. Any help would be appreciated. Thanks.

Find the place in your code where you expect the values to be changing, and examine the code carefully, to make sure you have it doing what you meant it to be doing. — Benjamin Lindley, Aug 19 '12 at 08:32
Please care to format your code properly. The indent is not obvious. — Ihor Kaharlichenko, Aug 19 '12 at 08:32
Side note: If you call `srand`, you should do it once near the start of the program; not every time you want to generate a pseudorandom number. — CB Bailey, Aug 19 '12 at 08:36
Read tags before you use them. This is NOT a question about the RPG Programming Language. This question probably belongs on gamedevelopment.stackexchange.com. — WarrenT, Aug 19 '12 at 16:24

AnT stands with Russia · Accepted Answer · 2012-08-19T08:51:29.813

Why would you expect these values to change? The only place in your program where you change the value of hp field is the Player::healSelf method. Since the player's HPs are capped at 100, and the player has 100 HP from the beginning, calling healSelf cannot rise the hp value above 100. This is why it doesn't change.

I would expect your getHit methods to change the hp value of player and enemy. But they don't. See for yourself

void Enemy::getHit(int atk)
{
   m_Stats.atk += m_Stats.def - atk;   
   m_Stats.def = 5;  
}

There's no mention of hp in that code. Apparenty, it is a bug. The same bug seems to be present in Player::getHit implementation.

Yup, that was the bug. I guess sometimes all that's required is a fresh pair of eyes. Thanks. — theSuperiorVenacava, Aug 19 '12 at 08:53

score 0 · Answer 2 · answered Aug 19 '12 at 08:34

0

From the looks of it, when you choose to "attack", you are calling e.getHit() which probably means the "enemy" is "hit". However, that function doesn't change the HP, it changes the ATK...

answered Aug 19 '12 at 08:34

Christian Stieber

9,954
24
23

Yes that was the main problem. Thanks a lot. – theSuperiorVenacava Aug 19 '12 at 08:53

score 0 · Answer 3 · answered Aug 19 '12 at 08:53

You are changing attack, not health.

Usually, a players defence determines how an attack is scaled.

void Player::getHit(int atk)
{
    m_Stats.atk += m_Stats.def - atk;     
}

If you assume that you have 100 hp, defence of 0.8 and someone attacks you for 20 points, you could do something like this:

void Player::getHit(int atk)
{
    m_Stats.hp -= m_Stats.def * atk;     
}

Your defence has hindered the attack, and you now have 84hp.

The value of the variables aren't changing in a simple text RPG game using C++

3 Answers3