#!/usr/bin/perl -w

use strict;

open DATA1, '<', \<<EOT;
1, 2
3, 4
EOT

open DATA2, '<', \<<EOT;
2, 4
6, 8
EOT

open DATA3, '<', \<<EOT;
3, 5
7, 9
EOT

while (<DATA1>) { print; }
print "\n";
while (<DATA2>) { print; }
print "\n";
while (<DATA3>) { print; }

exit 1;