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

use Data::Dump qw[ pp ];



#subroutine: read in hash tables

my $hash1=shift;
 open (my $fh1, "<",$hash1) or die "$!";  
    my %h1=();
    while (<$fh1>) {
        chomp;
        my ($k1,$v1)=split /\t/;
        $h1{$k1}=$v1;
}

my $hash2=shift;
 open (my $fh2, "<",$hash2) or die "$!";  
    my %h2=();
    while (<$fh2>) {
        chomp;
        my ($k2,$v2)=split /\t/;
        $h2{$k2}=$v2;
}

my %newhash = map {
    $_ => join ',', @h2{ split ',', $h1{ $_ } };
} keys %h1;

while (my ($k, $v) = each %newhash) {
    print $k, "\t@{$newhash{$k}}\n";
}