#!/usr/bin/perl
# ---------------------------------- #
# Three Card Game paradox three.pl
# by Conor Gilmer
# ---------------------------------- # 

use strict;
use warnings;

my $winning;		# var for winning card
my $chosen;		# var for chosen card
my $remove;		# var for random wrong card to be removed
my $twist	= 0;	# counter for number of winning twists
my $stick	= 0;	# counter for number of winning sticks;
my $x;

my @cards       = ('A', 'B', 'C');	# array of cards

sub run
{
	print ("Three cards ( @cards )\n");
	#winning card picked (random)
	$winning = int(rand(3)); #cast the random number to an integer
	#card selected (random)
	$chosen = int(rand(3));
	
	#remove one wrong card
	do {
		$remove = int(rand(3));
	} while (($cards[$remove] eq $cards[$chosen]) || ($cards[$remove] eq $cards[$winning]) );
	
	print("Choose $cards[$chosen] | Removed $cards[$remove]\n");

	#stick or twist
	print("Winning Card is $cards[$winning]");
	if ($winning == $chosen) 	{
		print (" - Sticking wins\n");
		$stick++;
	}
	else {
		print (" - Twisting wins\n");
		$twist++;
	}
}

sub main
{	my $games = shift;
	my $percentageS;
	my $percentageT;
	print ("\n");
	print ("Three Card Game Paradox \n");
	# run 1000 times
	for (my $i=1; $i<($games+1); $i++)
	{
	   print "Game: $i\n";
	   run();
	}
	print("\nGame played $games times\n");
	$percentageS = 100 * ($stick/$games);
	$percentageT = 100 * ($twist/$games);
	print("Results:\n");
	print("Sticking wins $stick ($percentageS %)times \nTwisting wins $twist ($percentageT %) times\n");
	print("The End\n");
}

# check if the passed parameter is a number
sub is_integer {
   defined $_[0] && $_[0] =~ /^[+-]?\d+$/;
}



#get input argument (number of times to run)
$x = shift(@ARGV);

# run main value passed or default 1000 times
if (($x ne "") && (is_integer($x))) {
	main($x);
} else	{
	main(1000);
}