#!/usr/bin/env perl

use strict;
use warnings;

use List::Util qw{first};

use constant {
    HOUSE  => 0,
    FAMILY => 1,
    EXTERN => 2,
    EXTRAS => 3
};

use constant INDEX => qw{HOUSE FAMILY EXTERN EXTRAS};

my @table;

while (<DATA>) {
    push @table, [ split ];
}

print crosslink(HOUSE, FAMILY, 9), "\n";
print crosslink(HOUSE, FAMILY, 9), "\n";
print crosslink(FAMILY, HOUSE, 10), "\n";
print crosslink(EXTRAS, EXTERN, '8text'), "\n";
print crosslink(EXTRAS, FAMILY, '8text'), "\n";
print crosslink(HOUSE, EXTRAS, 12), "\n";
print crosslink(HOUSE, EXTRAS, 13), "\n";

{
    my %cross;

    sub crosslink {
        my ($in, $out, $val) = @_;

        my $key = $in . '-' . $val;

        if (exists $cross{$key}) {
            return $cross{$key}[$out];
        }

        print 'Search once only:', "\n";   # for testing only - remove in production
        my $found = first { $_->[$in] eq $val } @table;

        return 'Not found! ' . (INDEX)[$in] . ": $val" if ! defined $found;

        $cross{$key} = $found;

        return $cross{$key}[$out];
    }
}

__DATA__
1   2   3   4text
5   6   7   8text
9   10  11  12text
13  14  15  16text