How to increment number after letter in PHP - php

Question

I'm looking to increment a number after a certain letter.
I have a list of own Ids and i would like to increment it without write it manually each time i add a new id.
$ids = array('303.L1', '303.L2', '303.L3', '303.L4');
so i use the END() function to extract the last id from this array.
this is what i've tried but i cannot get a result.
$i = 0;
while($i <= count($ids)){
$i++;
$new_increment_id = 1;
$final_increment = end($last_id) + $new_increment_id;
}
echo $final_increment;
New method, but it is adding me double dot between number and letter.
$i = 0;
while($i <= count($ids)){
$i++;
$chars = preg_split("/[0-9]+/", end($ids));
$nums = preg_split("/[a-zA-Z]+/", end($ids));
$increment = $nums[1] + 1;
$final_increment = $nums[0].$chars[1].$increment;
}
//i will use this id to be inserted to database as id:
echo $final_increment;
Is there another way to increment the last number after L ?
Any help is appreciated.

Answer 1

If you don't want a predefined list, but you want a defined number of ids returned in an $ids variable u can use the following code
<?php
$i = 0;
$number_of_ids = 4;
$id_prefix = "303.L";
$ids = array();
while($i < $number_of_ids){
$ids[] = $id_prefix . (++$i); // adds prefix and number to array ids.
}
var_dump($ids);
// will output '303.L1', '303.L2', '303.L3', '303.L4'
?>

Answer 2

I'm a bit confused because you say "without write it manually". But I think I have a solution:
$ids = array('303.L1', '303.L2', '303.L3', '303.L4');
$i = 0;
while($i <= count($ids)){
++$i;
//Adding a new item to that array
$ids[] = "303.L" . $i;
}
This would increment just that LAST number, starting at zero. If you wanted to continue where you left off, that'd be simple too. Just take $i = 0; and replace with:
//Grab last item in array
$current_index = $ids[count($ids) - 1];
//Separates the string (i.e. '303.L1') into an array of ['303', '1']
$exploded_id = explode('.L', $current_index);
//Then we just grab the second item in the array (index 1)
$i = $exploded_id[1];