#!/usr/bin/perl

# http://perlmonks.org/?node_id=1162755

use strict;
use warnings;

my %score;
chomp(my @array = <DATA>);

for my $i (1..@array)
  {
  $score{$1}[$-[0]] += 1/@array while $array[$i - 1] =~ /(.)/g;
  }

printf " " . "%5s  " x @array . "\n", sort keys %score;
for my $pos ( 1..length $array[0] )
  {
  printf "%1d" . "%7.2f" x @array . "\n",
    $pos, map { $score{$_}[$pos - 1] // 0  } sort keys %score;
  }

__DATA__
AABBC
BAABC
AABBD
AACBB
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