Task

Implement the classic children's game Rock-paper-scissors, as well as a simple predictive   AI   (artificial intelligence)   player.

Rock Paper Scissors is a two player game.

Each player chooses one of rock, paper or scissors, without knowing the other player's choice.

The winner is decided by a set of rules:

   Rock beats scissors
   Scissors beat paper
   Paper beats rock


If both players choose the same thing, there is no winner for that round.

For this task, the computer will be one of the players.

The operator will select Rock, Paper or Scissors and the computer will keep a record of the choice frequency, and use that information to make a weighted random choice in an attempt to defeat its opponent.



Extra credit

Support additional choices   additional weapons.




 
#include <windows.h>
#include <iostream>
#include <string>
 
//-------------------------------------------------------------------------------
using namespace std;
 
//-------------------------------------------------------------------------------
enum choices { ROCK, SPOCK, PAPER, LIZARD, SCISSORS, MX_C };
enum indexes { PLAYER, COMPUTER, DRAW };
 
//-------------------------------------------------------------------------------
class stats
{
public:
    stats() : _draw( 0 )
    {
        ZeroMemory( _moves, sizeof( _moves ) );
	ZeroMemory( _win, sizeof( _win ) );
    }
    void draw()		        { _draw++; }
    void win( int p )	        { _win[p]++; }
    void move( int p, int m )   { _moves[p][m]++; }
    int getMove( int p, int m ) { return _moves[p][m]; }
    string format( int a )
    {
	char t[32];
	wsprintf( t, "%.3d", a );
	string d( t );
	return d;
    }
 
    void print()
    {
        string  d = format( _draw ),
	       pw = format( _win[PLAYER] ),		cw = format( _win[COMPUTER] ),
	       pr = format( _moves[PLAYER][ROCK] ),	cr = format( _moves[COMPUTER][ROCK] ),
               pp = format( _moves[PLAYER][PAPER] ),	cp = format( _moves[COMPUTER][PAPER] ),
	       ps = format( _moves[PLAYER][SCISSORS] ), cs = format( _moves[COMPUTER][SCISSORS] ),
	       pl = format( _moves[PLAYER][LIZARD] ),	cl = format( _moves[COMPUTER][LIZARD] ),
	       pk = format( _moves[PLAYER][SPOCK] ),	ck = format( _moves[COMPUTER][SPOCK] );
 
	system( "cls" );
	cout << endl;
	cout << "+----------+-------+--------+--------+---------+----------+--------+---------+" << endl;
	cout << "|          |  WON  |  DRAW  |  ROCK  |  PAPER  | SCISSORS | LIZARD |  SPOCK  |" << endl;
	cout << "+----------+-------+--------+--------+---------+----------+--------+---------+" << endl;
	cout << "|  PLAYER  |  "  << pw << "  |        |   " << pr << "  |   " << pp << "   |   " << ps << "    |  " << pl << "   |   " << pk << "   |" << endl;
	cout << "+----------+-------+   " << d << "  +--------+---------+----------+--------+---------+" << endl;
	cout << "| COMPUTER |  "  << cw << "  |        |   " << cr << "  |   " << cp << "   |   " << cs << "    |  " << cl << "   |   " << ck << "   |" << endl;
	cout << "+----------+-------+--------+--------+---------+----------+--------+---------+" << endl;
	cout << endl << endl;
 
	system( "pause" );
 
    }
 
private:
    int _moves[2][MX_C], _win[2], _draw;
};
//-------------------------------------------------------------------------------
class rps
{
private:
    int makeMove()
    {
	int total = 0, r, s;
	for( int i = 0; i < MX_C; total += statistics.getMove( PLAYER, i++ ) );
	r = rand() % total;
 
	for( int i = ROCK; i < SCISSORS; i++ )
	{
	    s = statistics.getMove( PLAYER, i );
	    if( r < s ) return ( i + 1 );
	    r -= s;
	}
 
	return ROCK;
    }
 
    void printMove( int p, int m )
    {
	if( p == COMPUTER ) cout << "My move: ";
	else cout << "Your move: ";
 
	switch( m )
	{
	    case ROCK: cout << "ROCK\n"; break;
	    case PAPER: cout << "PAPER\n"; break;
	    case SCISSORS: cout << "SCISSORS\n"; break;
	    case LIZARD: cout << "LIZARD\n"; break;
	    case SPOCK: cout << "SPOCK\n";
	}
    }
 
public:
    rps()
    {
	checker[ROCK][ROCK] = 2; checker[ROCK][PAPER] = 1; checker[ROCK][SCISSORS] = 0; checker[ROCK][LIZARD] = 0; checker[ROCK][SPOCK] = 1;
	checker[PAPER][ROCK] = 0; checker[PAPER][PAPER] = 2; checker[PAPER][SCISSORS] = 1; checker[PAPER][LIZARD] = 1; checker[PAPER][SPOCK] = 0;
	checker[SCISSORS][ROCK] = 1; checker[SCISSORS][PAPER] = 0; checker[SCISSORS][SCISSORS] = 2; checker[SCISSORS][LIZARD] = 0; checker[SCISSORS][SPOCK] = 1;
	checker[LIZARD][ROCK] = 1; checker[LIZARD][PAPER] = 0; checker[LIZARD][SCISSORS] = 1; checker[LIZARD][LIZARD] = 2; checker[LIZARD][SPOCK] = 0;
	checker[SPOCK][ROCK] = 0; checker[SPOCK][PAPER] = 1; checker[SPOCK][SCISSORS] = 0; checker[SPOCK][LIZARD] = 1; checker[SPOCK][SPOCK] = 2;
    }
    void play()
    {
	int p, r, m;
	while( true )
	{
	    cout << "What is your move (1)ROCK (2)SPOCK (3)PAPER (4)LIZARD (5)SCISSORS (0)Quit ? ";
	    cin >> p;
	    if( !p || p < 0 ) break;
	    if( p > 0 && p < 6 )
	    {
		p--;
		cout << endl;
		printMove( PLAYER, p );
		statistics.move( PLAYER, p );
 
		m = makeMove();
		statistics.move( COMPUTER, m );
		printMove( COMPUTER, m );
 
		r = checker[p][m];
		switch( r )
		{
		    case DRAW: 
		        cout << endl << "DRAW!" << endl << endl; 
		        statistics.draw();
		    break;
		    case COMPUTER: 
			cout << endl << "I WIN!" << endl << endl;  
			statistics.win( COMPUTER );
		    break;
		    case PLAYER: 
			cout << endl << "YOU WIN!" << endl << endl; 
			statistics.win( PLAYER );
 
		}
		system( "pause" );
	    }
	    system( "cls" );
	}
	statistics.print();
    }
 
private:
    stats statistics;
    int checker[MX_C][MX_C];
};
//-------------------------------------------------------------------------------
int main( int argc, char* argv[] )
{
    srand( GetTickCount() );
    rps game;
    game.play();
    return 0;
}
//-------------------------------------------------------------------------------
 