Stumped on Rock Paper Scissors against Computer

[dkwtfimdoing845]

Hello everyone. So I need to create Rock, Paper, Scissors game with player 1 being a user and player 2 being the computer. Most of this code was provided by the professor but I fiddled with some of it. Player2 is the only function I created.

The original code had player 2 as another user. In order to change player 2 to the computer, I figured I need to make a function that generates a random number between 1 and 3 and then assigns that number to enum ROCK, PAPER, SCISSOR.

I spent nearly 10 hours trying to get Player2() to be useful but it barely runs. Now it's simply providing 9 digit numbers all throughout the code when I compile it. It's also giving me a run time error.

Is there a better way to generate a random number? Is it possible for me to assign numbers to enum types? Should the Player2 function be embedded into one of the existing functions? How can I bring a useful obejectType into the Player2 function? What about my number generator is causing 9 digit numbers to form?

Any guidance is greatly appreciated!

  #include <iostream>
#include <fstream>
#include <cstdlib>
#include <ctime>

using namespace std;

enum objectType { ROCK, PAPER, SCISSORS };



//Function prototypes
void displayRules();
objectType retrievePlay(char selection);
int Player2();
bool validSelection(char selection);
void convertEnum(objectType object);
objectType winningObject(objectType play1, objectType play2);
void gameResult(objectType play1, objectType play2,
	int& winner);
void displayResults(int gCount, int wCount1, int wCount2);

int main()
{


	//srand(time(NULL));
	//Step 1
	int gameCount; //variable to store the number of
				   //games played
	int winCount1; //variable to store the number of games
				   //won by player 1
	int winCount2; //variable to store the number of games
				   //won by player 2
	int gamewinner;
	char response;  //variable to get the user's response to
					//play the game
	char selection1;
	//int selection2;

	objectType play1;  //player1's selection
					   //objectType play2;  //player2's selection
	objectType play2;
	//Initialize variables; Step 2
	gameCount = 0;
	winCount1 = 0;
	winCount2 = 0;

	displayRules();                               //Step 3

	int compChoice;
	compChoice = Player2();

	cout << "Enter Y/y to play the game: ";       //Step 4
	cin >> response;                              //Step 5
	cout << endl;

	while (response == 'Y' || response == 'y')   //Step 6
	{
		cout << "Player 1 enter your choice: ";   //Step 6a
		cin >> selection1;                        //Step 6b
		cout << endl;

		//cout << "Player 2 enter your choice: ";   //Step 6c
		cout << "The computer chose: " << Player2();                      
 //Step 6d
 //cout << endl;
//Step 6e
		if (validSelection(selection1)
			&& Player2())
		{
			play1 = retrievePlay(selection1);
			play2 = retrievePlay(compChoice);
			gameCount++;                          //Step 6e.i
			gameResult(play1, play2, gamewinner); //Step 6e.ii

			if (gamewinner == 1)                  //Step 6e.iii
				winCount1++;
			else if (gamewinner == 2)
				winCount2++;
		}//end if

		cout << "Enter Y/y to play the game: ";   //Step 6f
		cin >> response;                          //Step 6g
		cout << endl;
	}//end while

	displayResults(gameCount, winCount1,
		winCount2);                    //Step 7

	return 0;
}//end main

void displayRules()
{
	cout << "  Welcome to the game of Rock, Paper, "
		<< "and Scissors." << endl;
	cout << "This is a game for two players. The second "
		<< "player is the computer." << endl;
	cout << "For each game, each" << endl;
	cout << " player selects one of the objects, Rock, "
		<< "Paper or Scissors." << endl;
	cout << " The rules for winning the game are: " << endl;
	cout << "1. If both players selects the same object, it "
		<< "is a tie." << endl;
	cout << "2. Rock breaks Scissors: So player who selects "
		<< "Rock wins." << endl;
	cout << "3. Paper covers Rock: So player who selects "
		<< "Paper wins." << endl;
	cout << "4. Scissors cuts Paper: So player who selects "
		<< "Scissors wins." << endl << endl;
	cout << "Enter R or r to select Rock, P or p to select "
		<< "Paper, and S or s to select Scissors." << endl;
}

bool validSelection(char selection)
{
	switch (selection)
	{
	case 'R':
	case 'r':
	case 'P':
	case 'p':
	case 'S':
	case 's':
	case '1':
	case '2':
	case '3':
		return true;
	default:
		return false;
	}
}


objectType retrievePlay(char selection)
{
	objectType object;
	//objectType compChoice = static_cast<objectType>(rand()%3 + 1);

	switch (selection)
	{
	case 'R':
	case 'r':
	case '1':
		object = ROCK;
		break;
	case 'P':
	case 'p':
	case '2':
		object = PAPER;
		break;
	case '3':
	case 'S':
	case 's':
		object = SCISSORS;
	}

	return object;
}

void convertEnum(objectType object)
{
	switch (object)
	{
	case ROCK:
		cout << "Rock";
		break;
	case PAPER:
		cout << "Paper";
		break;
	case SCISSORS: cout << "Scissors";
	}
}

objectType winningObject(objectType play1, objectType play2)
{
	if ((play1 == ROCK && play2 == SCISSORS)
		|| (play2 == ROCK && play1 == SCISSORS))
		return ROCK;
	else if ((play1 == ROCK && play2 == PAPER)
		|| (play2 == ROCK && play1 == PAPER))
		return PAPER;
	else
		return SCISSORS;
}

void gameResult(objectType play1, objectType play2,
	int& winner)
{
	objectType winnerObject;

	if (play1 == play2)
	{
		winner = 0;
		cout << "Both players selected ";
		convertEnum(play1);
		cout << ". This game is a tie." << endl;
	}
	else
	{
		winnerObject = winningObject(play1, play2);

		//Output each player's choice
		cout << "Player 1 selected ";
		convertEnum(play1);
		cout << " and player 2 selected ";
		convertEnum(play2);
		cout << ". ";

		//Decide the winner
		if (play1 == winnerObject)
			winner = 1;
		else if (play2 == winnerObject)
			winner = 2;

		//Output the winner
		cout << "Player " << winner << " wins this game."
			<< endl;
	}
}
int Player2()
{
	int compChoice;
	//srand(time(0));
	compChoice = rand() % 3 + 1;


	if (compChoice == 1)
	{

		compChoice = retrievePlay('r');
		cout << retrievePlay << endl;
	}
	else if (compChoice == 2)
	{
		compChoice = retrievePlay('p');
		cout << retrievePlay << endl;
	}
	else
	{
		compChoice = retrievePlay('s');
		cout << retrievePlay << endl;
	}

	return (compChoice);
}

void displayResults(int gCount, int wCount1, int wCount2)
{
	cout << "The total number of plays: " << gCount
		<< endl;
	cout << "The number of plays won by player 1: "
		<< wCount1 << endl;
	cout << "The number of plays won by player 2: "
		<< wCount2 << endl;
}

[keskiverto]

Lines 233, 238, 243: What is this "value" retrievePlay that you print?

[AbstractionAnon]

Line 27: Uncomment this line. This is the correct place to seed the RNG.

Line 52: Why are you calling Player2() here?

Line 65: Player2() is going to return a random value and that is going to be displayed. But that value is not going to be used at line 73. Should be this instead:

    compChoice = Player2();
    cout << "The computer chose: " << compChoice << endl;         

Line 54: It's a little silly asking here if you want to play the game. Initialize response to 'Y' instead.

Line 83: This should say "Play again?"

Line 233, 238, 243: You're displaying the address of the function. You're not calling the function. This is why you're getting 8 digits. Since you set compChoice on the previous line, you really want to be displaying compChoice.

Line 141: You have problems with this switch statement. You have cases for ASCII '1', '2' and '3'. However the values of your enum are binary 0, 1, 2.

Line 226: Your random number is not going to line up with your enum. enums, if not explicitly assigned, start at 0. Your random number is going to be 1-3.

[JLBorges]

A data driven approach would be simpler. Something along these lines:

#include <iostream>
#include <cctype>
#include <cstdlib>
#include <ctime>

enum object { ROCK, PAPER, SCISSORS, NUM_OBJECTS, INVALID = -1 };
const char* const object_name[NUM_OBJECTS] = { "Rock", "Paper", "Scissors" } ;

const bool result[NUM_OBJECTS][NUM_OBJECTS] = { { 0, 0, 1 }, { 1, 0, 0 }, { 0, 1, 0 } } ;

const char* const msg[NUM_OBJECTS][NUM_OBJECTS] =
{
    { "It is a tie!", "Paper wins. Paper covers Rock", "Rock wins. Rock breaks Scissors" },
    { "Paper wins. Paper covers Rock", "It is a tie!", "Scissors wins. Scissors cuts Paper" },
    { "Rock wins. Rock breaks Scissors", "Scissors wins. Scissors cuts Paper", "It is a tie!" },
};

object char_to_object( char c )
{
    c = std::toupper(c) ;
    for( int i = 0 ; i < NUM_OBJECTS ; ++i ) if( object_name[i][0] == c ) return object(i) ;
    return INVALID ;
}

object choose_object()
{
    std::cout << "\nenter your choice R/P/S [(R)ock (P)aper (S)cissors]: " ;
    char c ;
    std::cin >> c ;

    object obj = char_to_object(c) ;
    if( obj != INVALID )
    {
        std::cout << "Player chooses " << object_name[obj] << '\n' ;
        return obj ;
    }

    std::cout << "invalid input. try again\n" ;
    return choose_object() ;
}

object generated_choice()
{
    const auto obj = object( std::rand() % NUM_OBJECTS ) ;
    std::cout << "Computer chooses " << object_name[obj] << '\n' ;
    return obj ;
}

bool again()
{
    std::cout << "\nplay again? (Y/N)? " ;
    char c ;
    std::cin >> c ;
    return c == 'y' || c == 'Y' ;
}

int main()
{
    std::srand( std::time(nullptr) ) ;

    int num_wins_player = 0 ;
    int num_wins_computer = 0 ;
    int num_ties = 0 ;

    do
    {
        const object one = choose_object() ;
        const object two = generated_choice() ; // choose_object(2) ;

        std::cout << "\nPlayer's " << object_name[one] << " vs Computer's " << object_name[two] << '\n'
                  << "result: " << msg[one][two] << '\n' ;

        if( one == two ) ++num_ties ;
        else if( result[one][two] ) ++num_wins_player ;
        else ++num_wins_computer ;

        std::cout << "\nResult so far:\n------------\n"
                  << "          total: " << num_wins_player + num_wins_computer + num_ties << '\n'
                  << "  won by player: " << num_wins_player << '\n'
                  << "won by computer: " << num_wins_computer << '\n'
                  << "           ties: " << num_ties << '\n' ;
    }
    while( again() ) ;
}