- sscanf: documentation ( source)
- date: documentation ( source)
- strtotime: documentation ( source)
<?php
$date = "30-12-1899 9:25:52 AM";
sscanf($date, "%d-%d-%d %d:%d:%d %s", $d, $m, $Y, $g, $i, $s, $A);
$h = $A == 'AM' ? $g : $g + 12;
$date = "$Y-$m-$d $h:$i:$s";
$date = strtotime($date);
echo date('H:i:s', $date);