#!/usr/bin/perl use strict; use warnings; my $desired_postage = $ARGV[0] || 1.51; $desired_postage = int $desired_postage * 100; my @stamps = sort { $a <=> $b } grep { chomp; $_ < $desired_postage } map { int $_ * 100 } grep { ! /^#/ } ; my $exact = grep { $_ == $desired_postage } @stamps; print "Exact postage: " . $exact / 100 . "\n" if $exact; my $dim_max = 6; recurse( $desired_postage, [] ); sub recurse { my( $rest, $select ) = @_; if ( $rest == 0 ) { print $_ / 100 . " " for @$select; print "\n"; return; } return if @$select >= $dim_max; my @filtered = grep { $_ >= $rest / ($dim_max - @$select) and $_ <= $rest } @stamps; @filtered = grep{ $_ <= $select->[-1] } @filtered if $select->[-1]; for my $stamp ( sort{ $b <=> $a } @filtered ) { recurse( $rest - $stamp, [ @$select, $stamp ] ); } return; }