open my $RD, '<', 'input.txt' or die "Cannot open 'input.txt' $!";

open my $WR2, '>>', 'output.txt' or die "Cannot open 'output.txt' $!";

my $C = qr/1999-1041/;

my $count = 0;

while ( <$RD> ) {
    $count += /$C/;
    }

print $WR2 "$C ", $count ? '' : 'not ', "found in file 'input.txt'.\n";