use strict; use warnings; use Data::Dump qw/pp dd/; # my @freq = qw/5 7 10 15 20 45/; # my $sym = "1"; # my @tree = map { [ $_ => $sym++ ] } @freq; my %freq = ( "" => 592, "2" => 74, "24" => 60, "246" => 24, "247" => 24, "248" => 24, "249" => 24, "25" => 84, "257" => 24, "258" => 24, "259" => 24, "26" => 84, "268" => 24, "269" => 24, "27" => 84, "279" => 24, "28" => 84, "29" => 60, "3" => 208, "35" => 144, "357" => 48, "358" => 48, "359" => 48, "36" => 192, "368" => 48, "369" => 48, "37" => 192, "379" => 48, "38" => 192, "39" => 144, "4" => 366, "46" => 228, "468" => 72, "469" => 72, "47" => 300, "479" => 72, "48" => 300, "49" => 228, "5" => 524, "57" => 312, "579" => 96, "58" => 408, "59" => 312, "6" => 682, "68" => 396, "69" => 396, "7" => 840, "79" => 336, "8" => 830, "9" => 508, ); my @tree = map { [ $freq{$_} => $_ ] } keys %freq; #warn pp \@tree; #exit; while ( @tree > 1 ) { @tree = sort { $a->[0] <=> $b->[0] } @tree; my $left = shift @tree; my $right = shift @tree; unshift @tree, [ ($left->[0] + $right->[0]) => [ $left, $right ] ]; } #warn pp \@tree; my %huff; create_code($tree[0],""); #warn pp \%huff; my $avr = 0; $avr += $freq{$_} * length($huff{$_}) / 10000 for keys %freq; my $classic = log(50)/log(2); my $old=0; $old += $freq{$_} * length($_) * 8 / 10000 for keys %freq; $old += 8/9 ; # \n warn pp { "old" => $old, "line" => $old*9/8 . " bytes", "huff average" => $avr , "classic length" => $classic , "huff win" => $avr/$old*100 ." %", "classic win" => $classic/$old*100 ." %", }; sub create_code { my ($node,$code) = @_; my $sym = $node->[1]; if ( ref $sym ) { create_code( $sym->[0], $code."0" ); create_code( $sym->[1], $code."1" ); } else { $huff{$sym} = $code; } }