How to increment letters like numbers in PHP?

Question

I would like to write a function that takes in 3 characters and increments it and returns the newly incremented characters as a string.

I know how to increase a single letter to the next one but how would I know when to increase the second letters and then stop and then increase the first letter again to have a sequential increase?

So if AAA is passed, return AAB. If AAZ is passed return ABA (hard part).

I would appreciate help with the logic and what php functions will be useful to use.

Even better, has some done this already or there is a class available to do this??

Thanks all for any help

Answer 1

Character/string increment works in PHP (though decrement doesn't)

$x = 'AAZ'; $x++; echo $x;  // 'ABA' 

Answer 2

You can do it with the ++ operator.

$i = 'aaz'; $i++; print $i; 

aba

However this implementation has some strange things:

for($i = 'a'; $i < 'z'; $i++) print "$i "; 

This will print out letters from a to y.

for($i = 'a'; $i <= 'z'; $i++) print "$i "; 

This will print out lettes from a to z and it continues with aa and ends with yz.