<?php
	$data = Array(
		0 => "01:01:00",
		1 => "01:01:01",
		2 => "01:01:02",
		3 => "01:01:02",
		4 => "01:01:03",
		5 => "01:01:04"
	);
	$firstPosition = array_search("01:01:02", $data);
	echo "First: ".$firstPosition."\n";
	$lastPosition = array_search("01:01:02", array_reverse($data, true));
	echo "Last: ".$lastPosition;