Im trying to get hold of how to get the difference between two mysql varchar strings they are of the format mm:ss where m stands for minutes and s for seconds. So for instance.
$a = 13:20;
$b = 13:00;
what function do I use so that
$a - $b = 00:20 ?
$a = strtotime('13:20');
$b = strtotime('13:00');
echo "The time difference between 13:20 and 13:00 is : " . ($a - $b);
Gives me
The time difference between 13:20 and 13:00 is : 1200
Kindly take note of my original format. mm:ss