if ($line2 =~ /^\@\S+\s+ILLUMINA\S+:(\d+):(\d+):(\d+):(\d+)\s+length=160/) {
	$x2 = $3;
	$y2 = $4;
} else {
	die "problem: line is $line\n";
	#problem: now line is @SRR254172.1 ILLUMINA-20A1B2_0004_FC6282EAAXX:6:1:1433:941 length=160
}