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

my %listbyver;
my %listbyname;

sub versort {
    my @aa = split /\./, $a;
    my @bb = split /\./, $b;
    $aa[0] <=> $bb[0] || $aa[1] <=> $bb[1] || $aa[2] <=> $bb[2];
}

sub getdir {
    opendir(my $dir, '.');
    my @file = readdir($dir);
    closedir($dir);

    my @verx;

    for (grep /(\d+)\.(\d+)\.(\d+)/, @file){
	push @verx, $_;
    }

    return (sort versort @verx);
}

{
    {
	my @ver = getdir();
	
	for my $v (@ver){
	    opendir (my $dir2, $v);
	    my @file = sort(grep /perl.*\.pod/, readdir($dir2));
	    $listbyver{$v} = \@file;
	    for (@file){
		my @x = @{$listbyname{$_}};
		push @x, $v;
		$listbyname{$_} = \@x;
	    }
	}
    }

    
}