#!/usr/bin/perl
use strict;
use warnings;

#
# Everything here is very brute-force and hackish
# as befits a combat-related program
#

sub probability_to_beat
{
    my @defender_roll = sort { $b <=> $a } @{ +shift };
    my @attackers = @_;

    my @lose = (0) x 3;         # none, one, two
    foreach my $attacker_roll (@attackers) {
        my @attacker_roll = sort { $b <=> $a } @$attacker_roll;
        my $lost = 0;
        for (0..(@$attacker_roll > @defender_roll
                 ? $#defender_roll : $#$attacker_roll)) {
            ++$lost if ($defender_roll[$_] >= $attacker_roll[$_]);
        }
        ++$lose[$lost];
    }

    return @lose;
}

sub dice {
    my $n = shift;
    return ($n == 0)
      ? [[]]
      : [map {
            my $first = $_;
            map [@$first, $_], 1..6
        } @{dice($n-1)}]
    ;
}


sub run
{
    my @attackers = @{ +shift };
    my @defenders = @{ +shift };
    my $num_attackers = scalar @{ $attackers[0] };
    my $num_defenders = scalar @{ $defenders[0] };

    my @total_lose = (0) x 3;
    foreach my $defender_roll (@defenders) {
        my @lose =
          probability_to_beat( $defender_roll, @attackers );
        my $total = $lose[0] + $lose[1] + $lose[2];
        print join( ', ' => @$defender_roll) . "\t" . 
          sprintf("%2.2f%%, %2.2f%%, %2.2f%%", 
                  ($lose[0]  / $total) * 100,
                  ($lose[1]  / $total) * 100,
                  ($lose[2]  / $total) * 100,
                 ) . "\n";
        $total_lose[0]  += $lose[0];
        $total_lose[1]  += $lose[1];
        $total_lose[2]  += $lose[2];
    }

    my $total = $total_lose[0] + $total_lose[1] + $total_lose[2];

    print "Totals:\t" . 
      sprintf("%2.2f%%, %2.2f%%, %2.2f%%", 
              ($total_lose[0] / $total) * 100,
              ($total_lose[1] / $total) * 100,
              ($total_lose[2] / $total) * 100,
             ) . "\n";
}


for my $a_dice (3,2,1) {
    for my $d_dice (2,1) {
        print "$a_dice v $d_dice\n";
        run(dice($a_dice), dice($d_dice));
    }
}
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