use strict;
my @responses = (500, 300, 200, 400, 500, 300, 200, 500, 400, 500);
while (<DATA>) {
	chomp;
	my $response = $responses[$_];
	unless ($response == 200) {
		next if $response == 500;
		print "[$_] $response\n";
	}
}

__DATA__
0
1
2
3
4
5
6
7
8
9

##</code><code>##

[1] 300
[3] 400
[5] 300
[8] 400