24 uur, 15 min interval - PHP

gistfile1.txt

<?php

for($i = 0; $i <= 23; $i++) {
	// If hour is lower than 10, append a 0
	if($i < 10) {
		$append = 0;
	} else {
		$append = '';
	}
	
	// Echo hour + minute
	$minutes = 0;
	for($i2 = 1; $i2 <= 4; $i2++) {
		$minutes = ($i2 * 15) - 15;
		$minutes2 = ($minutes > 0) ? $minutes : $minutes . '0';
		echo $append . $i . ':' . $minutes2 . '<br>';
	}
}