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

my %test1;
open my $fh1, '<', 'test1.txt' or die "Open fail: $!";
while (<$fh1>) {
    my ($temp, $letter, undef, $number) = split;
    $test1{$temp}{$letter}{$number} = 1;
}

open my $fh, '<', 'test.txt' or die "Open fail: $!";
while (<$fh>) {
    my ($temp, $letter, undef, $number) = split;
    unless (defined $test1{$temp}{$letter}{$number}) {
        print;
    }
}