Question

Need help. I’m making electric billing system and I had a problem solving 2 numbers that has maximum of 99999 and after that it will back to 00000.I will give example:

1st  reading ==== 00050
2nd  reading ==== 00100
3rd  reading ==== 01000
4th  reading ==== 10000
nth  reading ==== 99950
last reading ==== 00050

how to solve nth and last reading?the answer must be 100…I’m using php codes

Answer 1

It’s hard to know exactly what you need without seeing your code but something like this would be the general approach:

// Assume you have $previous and $current
$difference = $current - $previous;
if ($difference < 0) {
    $difference = $current + (99999 - $previous);
}