#!/usr/bin/perl -w
use strict;
my $dicemax = shift @ARGV || 6;
my $numdice = shift @ARGV || 6;
my $dicekeep = shift @ARGV || 6;
my $samplesize = shift @ARGV || 0;

my $totstates = $dicemax ** $numdice;
my $min = $dicekeep;
my $max = $dicekeep * $dicemax;
my $num = $max - $min + 1;

my @tot; @tot[$min..$max] = map {0} ($min..$max);

if ($samplesize) {
  srand;
  for my $x (1..$samplesize) {
    my $sum=0;
    $sum += $_ for (sort {$b<=>$a}
                    map {int rand($dicemax)+1} (1..$numdice)
                   )[0..$dicekeep-1];
    $tot[$sum]++;
  }
  $totstates = $samplesize;
} else {
  my $count = 0;
  my @dice = map {1} (1..$numdice);
  while ($count++ < $totstates) {
    my $x = 0;
    $dice[$x]++;
    while ($dice[$x] > $dicemax) {
      $dice[$x++] = 1;
      $dice[$x]++;
    }
    my $sum=0;
    $sum += $_ for (sort {$b<=>$a} @dice)[0..$dicekeep-1];
    $tot[$sum]++;
  }
}

my @per; @per[$min..$max] = map {$_/$totstates*100} @tot[$min..$max];

my $maxper = (sort {$b<=>$a} @per[$min..$max])[0];

print "Roll Percent| Frequency Graph (0 - $maxper%)\n";
for my $x ($min..$max) {
  my $c = ($num-$x+$min)/$num*$maxper;
  printf "%3d   %5.2f | ", $x, $per[$x];
  do { print $per[$_] > $c ? "*" : " " for ($min..$max) }
    if $max-$min < 75;
  print "\n";
}
print "-"x(16+$max-$min),"\n";
for my $x (100,10,1) {
  print " "x14,map {int $_ / $x % 10} ($min..$max);
  print "\n";
}