#!/usr/bin/perl
# Incept: 1998-10-18 15:13:27 CDT (Oct Sun) http://www.talisman.org/~erlkonig/

# odds and score of 2d6
#            0 1   2   3   4   5   6    7   8   9  10   11 12
@odds   = (  0,0,  1,  2,  3,  4,  5,   6,  5,  4,  3,   2, 1 );
@scores = (  0,0, 10, 10, 40, 40, 40, -10, 40, 40, 40, -10, 0 );
$possibilities = 36;

sub main						# main routine, called near end of script
{
	my $score = 0;				# make a variable, for main only, named score
	$score = $ARGV[0] if($#ARGV >= 0); # look for a startscore on the cmdline

	# strings of characters (text) are concatenated (joined) with the dot
	print("initial score is " . $score . "\n");	# "\n" is a newline
	for(;;)						# forever, special case of for loop
	{
		print "------input roll: ";	# notice no \n
		my $roll = <STDIN>;		# read one line of input from standard in

		# regular expressions allows text to be described.  \d is a digit
		# + describes "one or more" of the thing to its left
		# hence, \d+ is "one or more" digits.  =~ triggers use of regexp
		if($roll =~ /\d+/)		# if input is a string of one or more digits
		{
			my $score_change = $scores[$roll]; # get score for specific roll
			print("odds of roll: " . $odds[$roll] . "/" .$possibilities ."\n");
			print("result of roll: " .  $score_change . "\n");
			$score += $score_change; # or: $score = $score + $score_change;
			print("updated score: " . $score . "\n");
		}
		else					# if the "if" failed (input wasn't a number)
		{
			print("quitting\n");
			last;				# would be "break" in C or the shells
		}
	}
	return 0;					# exit from nearest enclosing function (main)
}

&main;

#--------------------------------------------eof