RPG Battle Part 2

#include <iostream>
#include <string>
using namespace std;

int main()
{
void WaitForEnter();
int attack(int attackerATK, int victimHP, int victimDEF);
int heal(int oldHP);
int playerHP = 100;
int playerATK = 10;
int playerDEF = 5;
int monsterHP = 50;
int monsterATK = 10;
int monsterDEF = 5;
string userInput = "";
int tmpVar = 0;
int damage = 0;


while (monsterHP > 0 && playerHP > 0)
{
    //display HP for monster & player
    cout << "Monster HP: "<< monsterHP << endl
         << "Player HP: " << playerHP << endl;

    //display options (Attack, Heal)
    cout << "Attack" << endl
         << "Heal" << endl
         << "What would you like to do? ";

    getline(cin, userInput);

    //Validate
    while(userInput.compare("Attack") != 0 &&
        userInput.compare("Heal") != 0)
    {
        cout << "What would you like to do? ";
        getline(cin, userInput);
    }

    //Attack
    if(userInput.compare("Attack") == 0)
    {
        //player attack
        tmpVar = monsterHP;
        monsterHP = attack(playerATK, monsterHP, monsterDEF);
        damage = tmpVar - monsterHP;
        cout << "Player dealt " << damage << " damage!" << endl;

        //monster attack
        tmpVar = playerHP;
        playerHP = attack(monsterATK, playerHP, playerDEF);
        damage = tmpVar - playerHP;
        cout << "Monster dealt " << damage << " damage!" << endl;
    }

    //Heal
    if(userInput.compare("Heal") == 0)
    {

        //player heal
        tmpVar = playerHP;
        playerHP = heal(playerHP);
        cout << "Player Healed " << playerHP - tmpVar << " HP!" << endl;

        //monster attack
        tmpVar = playerHP;
        playerHP = attack(monsterATK, playerHP, playerDEF);
        damage = tmpVar - playerHP;
        cout << "Monster dealt " << damage << " damage!" << endl;
    }

}

cout << "Press Enter To Exit...";
WaitForEnter();

}

//Taken from Moosader (Rachel J. Morris)
void WaitForEnter(){ while(1) { if ('\n' == getchar() ) { break; } } }

//attack function
int attack(int attackerATK, int victimHP, int victimDEF)
{
    return (victimHP - rand()%(attackerATK - victimDEF));
}

//heal function
int heal(int oldHP)
{
    return (oldHP + rand()%5 + 1);
}