[showcase] guess my number with difficulty level

One of my assignments for class was to create a Guess my Number game using functions, passing parameters, validation, and writing to a file. I really do not use many comments in my code but I should start doing so.

Guess my Number game
- Asks user for their full name
- Asks user to set difficulty
- Asks user if they want to play
- User has five tries to guess
- Once user is finish, write to file with games played and games won with a score percentage.

Code:

---

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

//GUESS MY NUMBER W/FUNCTIONS BY CALL

//Prototypes
int getReply();
int getLevel();
int validateNumber(int, int);
void printResults(string, int, int);

int main()
{
//Housekeeping
        int number, guess, tries=0, level=0, upper=0, gamesPlayed=0, gamesWon=0;
        char reply;
        string playerName;
        srand((unsigned)time(0));

        cout << "State your full name please: ";
        getline(cin, playerName);
        cout << "Would you like to play the guessing game? (Y)es or (N)o? ";
        reply = getReply();
        cout << "Choose your level of difficulty (select a number from 1 to 10): ";
        level = getLevel();
        upper = level * 10;
        cout << "\nLet's play!";

        do
        {
                number=rand()%upper+1;
                gamesPlayed++;
                cout << "\n\nI am thinking of a number between 1 and " << upper << " \nCan you guess what it is? ";
               
                for(tries=5;tries>0;tries--)
                {
                        cin >> guess;
                        guess = validateNumber(guess, upper);
                        if (guess < number)
                        cout << "Your guess is low.  Try again: ";
                        else if (guess > number)
                        cout << "Your guess is high.  Try again: ";

                        if (guess==number)
                        {
                                cout << "Congratulations " << playerName << "! You did it.!";
                                gamesWon++;
                                break;
                        }
                }
                cout << endl;

                if(guess!=number)
                        cout << "Sorry " << playerName << ", The number was " << number << ".";

                cout << "\nWould you like to play again? ";
                reply = getReply();
               
        }while(reply == 'Y'); //Loop/Play again
       
        printResults(playerName, gamesPlayed, gamesWon);
       
        system("type results.txt");
    system("pause");
}

//Functions
int getReply()
{
        char answer;
       
        cin >> answer;
        answer = toupper(answer);

        while(answer != 'Y' && answer != 'N')
        {
                cin.clear();
                cin.ignore(80, '\n');
                cout << "Error: must be Y or N: ";
                cin >> answer;
                answer = toupper(answer);
        }

        cin.clear();
        cin.ignore(80, '\n');

        return answer;
}

int getLevel()
{
        int level;

        cin >> level;
        while(level < 1 || level > 10 || cin.fail())
        {
                cin.clear();
                cin.ignore(80,'\n');
                cout << "Error: number must be from 1-10: ";
                cin >>level;
        }
        return level;
}

int validateNumber(int number, int upper)
{
        while(number < 1 || number > upper || cin.fail())
        {
                cin.clear();
                cin.ignore(80,'\n');
                cout << "Error: number must be from 1-" << upper << ": ";
                cin >> number;
        }
        return number;
}

void printResults(string playerName, int gamesPlayed, int gamesWon)
{
        int percentage;
        percentage = (gamesWon/gamesPlayed)*100;

        ofstream fout("results.txt");
        if(!fout.is_open())
        {
                cout << "Error: could not find file.";
                system("pause");
                exit(666);
        }

        fout << setw(30) << left;
        fout << "Name: " << playerName;
        fout << setw(30) << right << "Score: " << percentage << "%";
        fout << endl << endl;
        fout << setw(30) << left << "Number of games played: " << gamesPlayed << endl;
        fout << setw(30) << "Number of games won: " << gamesWon << endl;
        cout << "\nAttention: saving to results.txt\n";
}

---