Guessing game multiplayer

[Vidminas]

I wrote the code for many mini games and they all work fine, except for the one, where a player plays against another player.
I removed all of the code for the other mini games.

#include <iostream>
#include <cstdlib>
#include <ctime>
#include <string>
#include <sstream>
#include <windows.h>

void playervsplayer();
void ClearScreen();

int main()
{
    srand(static_cast<unsigned int>(time(NULL)));
    bool running = true;
    int menuchoice, singleplayer, multiplayer;
    std::string input;

    do
    {
        while(true)
        {
            ClearScreen();

            std::cout << ":: Enter an option ::" << "\n\n";
            std::cout << "1. Single Player game" << "\n";
            std::cout << "2. Two Player game" << "\n";
            std::cout << "3. Automated game" << "\n";
            std::cout << "4. Exit" << "\n\n";
            getline(std::cin, input);
            std::stringstream myStream(input);
            if (myStream >> menuchoice)
            break;
            std::cout << "Please enter a valid number" << "\n";
            std::cout << "Press Enter to continue..." << "\n";
            std::cin.clear();
            std::cin.ignore(10000, '\n');
        }

        switch(menuchoice)
        {
            case 2:
                while(true)
                {
                    ClearScreen();
                    std::cout << "Choose who would you like to play against:" << "\n";
                    std::cout << "1. Your friend" << "\n";
                    std::cout << "2. The computer" << "\n";
                    getline(std::cin, input);
                    std::stringstream myStream(input);
                    if (myStream >> multiplayer)
                    break;
                    std::cout << "Please enter a valid number" << "\n";
                    std::cout << "Press Enter to continue..." << "\n";
                    std::cin.clear();
                    std::cin.ignore(10000, '\n');
                }

                switch(multiplayer)
                {
                case 1: playervsplayer(); break;
                
                default:
                std::cout << "Please choose one of the two games" << "\n\n";
                std::cin.clear();
                std::cin.ignore(10000, '\n');
                break;
                }
            break;

            case 4: running = false; break;

            default:
            std::cout << "Please choose one of the 3 types of games" << "\n\n";
            std::cin.clear();
            std::cin.ignore(10000, '\n');
            break;
        }
    } while (running);

    return 0;
}

void playervsplayer()
{
    std::string input, player1, player2;
    unsigned short player1guess, player2guess, gumballs = 0, turn = 0;
    gumballs = rand() % 1000 + 1;

    ClearScreen();
    std::cout << "Player 1, please enter your name: ";
    getline(std::cin, player1);
    std::cout << "\n" << "Welcome, " << player1 << "." << "\n\n";

    std::cout << "Player 2, please enter your name: ";
    getline(std::cin, player2);

        while (player2 == player1)
        {
            std::cout << "Player 1 has already chosen this name!" << "\n";
            std::cout << "Player 2, please enter your name: ";
            getline(std::cin, player2);
        }

    std::cout << "\n" << "Welcome, " << player2 << "." << "\n\n";

    std::cout << "In this game there is a gumball jar, which can hold up to 1000 gumballs." << "\n";
    std::cout << "Each player will have their turns to guess the amount of gumballs." << "\n";
    std::cout << "The player who gets it right first, wins!" << "\n\n";

    std::cout << "Let's begin!" << "\n\n";
    std::cout << "Press any key to continue..." << "\n";
    std::cout << "(Now where's the 'any' key?)" << "\n\n\n";
    std::cin.clear();
    std::cin.ignore(10000, '\n');

    std::cout << "Let's see who shall start... ";
    turn = rand() % 2 + 1;

    while (turn == 1)
    {
        std::cout << "It's " << player1 << "'s turn!" << "\n";
        while(true)
        {
            std::cout << "Enter your guess: ";
            getline(std::cin, input);
            std::stringstream myStream(input);
            if (myStream >> player1guess)
            break;
            std::cout << "Invalid number, please try again" << "\n";
        }

        if (player1guess > gumballs)
        {
        std::cout << "Nope, there are less!" << "\n\n";

        turn = 2;
        }

        else if (player1guess < gumballs)
        {
        std::cout << "Nope, there are more!" << "\n\n";
        turn = 2;
        }

        else
        {
        std::cout << "Hooray! You got it! You guessed the right amount of gumballs!!!" << "\n";
        std::cout << "Congratulations, " << player1 << ", you win!";
        std::cin.clear();
        std::cin.ignore(10000, '\n');
        }
    }

    while (turn == 2)
    {
        std::cout << "It's " << player2 << "'s turn!" << "\n";
        while(true)
        {
            std::cout << "Enter your guess: ";
            getline(std::cin, input);
            std::stringstream myStream(input);
            if (myStream >> player2guess)
            break;
            std::cout << "Invalid number, please try again" << "\n";
        }

        if (player2guess > gumballs)
        {
        std::cout << "Nope, there are less!" << "\n\n";
        turn = 1;
        }

        else if (player2guess < gumballs)
        {
        std::cout << "Nope, there are more!" << "\n\n";
        turn = 1;
        }

        else
        {
        std::cout << "Hooray! You got it! You guessed the right amount of gumballs!!!" << "\n";
        std::cout << "Congratulations, " << player2 << ", you win!";
        std::cin.clear();
        std::cin.ignore(10000, '\n');
        }
    }
}

void ClearScreen()
{
 //.. Let's save some space, shall we :P
}

My problem is that once a player guesses a number it either goes back to the main menu, or it let's the second player take a guess and then goes back to the main menu. This problem persists in both the full code and in this example.

I think that somehow the compiler is ignoring the while (turn == 1) and the while (turn == 2) loops.

P.S. I used this article for the getline() methods: http://www.cplusplus.com/forum/articles/6046/

[keineahnung]

Hi Vidminas
I don't have a Windows box to compile this on but it looks like a basic looping problem in your playervsplayer function.
I assume this line chooses either 1 or 2 at random and stores it in the variable, turn:
turn = rand() % 2 + 1;

Now see what follows:

while (turn == 1)
{
    // one turn only for player 1 - if they guess wrong, turn = 2
}
while (turn == 2)
{
    // one turn only for player 2 - if they guess wrong, turn = 1
}

Those while loops will execute at most once. If player 2 goes first, player 1 won't even get a look in.
You need an outer loop surrounding that whole routine. Something like:

bool playing_game = true;
turn = rand() % 2 + 1;
while ( playing_game )
{
    while (turn == 1)
    {
    // etc.
}

When a player wins the game, set playing_game to false to exit the outer loop.
Hope that helps.

[fg109]

Vidminas, don't even need while loops for those, just if statements inside a loop like keineahnung said.

bool playing_game = true;
turn = rand() % 2 + 1;
while ( playing_game )
{
    if (turn == 1)
    {
        //etc.
    }
    else //turn == 2
    {
        //etc.
    }
}

I think you also need std::cin.clear(); after these lines:

if (myStream >> player1guess)
    break;
std::cout << "Invalid number, please try again" << "\n";

[Vidminas]

I already had a do { } while (running); condition for my main menu, so instead i changed the while loops to if statements like you told me, then I put everything into a while(true) loop and added break; in case someone won.
It works now like it should :)