String mutation in array elements - php

Question

I would like to manipulate array elements. So if a certain array element ends with the letter n or m and the following element is for example apple then I want to delete the "a" of "apple" so that I get as an output: Array ( [0] => man [1] => pple )
My Code:
$input = array("man","apple");
$ending = array("m","n");
$example = array("apple","orange");
for($i=0;$i<count($input);$i++)
{
$second = isset( $input[$i+1])?$input[$i+1][0]:null;
$third = substr($input[$i],-2);
if( isset($third) && isset($second) ){
if ( in_array($third,$ending) && in_array($second,$example) ){
$input[$i+1] = substr($input[$i+1],0,-2);
}
}
}
How do I have to change my code so that I get the desired output?

Answer 1

Sounds like a cool exercise task.
My approach to this after reading the starting comments would be something like this:
$input = ['man', 'hamster', 'apple', 'ham', 'red'];
$endings = ['m', 'n'];
$shouldRemove = false;
foreach ($input as $key => $word) {
// if this variable is true, it will remove the first character of the current word.
if ($shouldRemove === true) {
$input[$key] = substr($word, 1);
}
// we reset the flag
$shouldRemove = false;
// getting the last character from current word
$lastCharacterForCurrentWord = $word[strlen($word) - 1];
if (in_array($lastCharacterForCurrentWord, $endings)) {
// if the last character of the word is one of the flagged characters,
// we set the flag to true, so that in the next word, we will remove
// the first character.
$shouldRemove = true;
}
}
var_dump($input);
die();
The output of this script would be
array(5) { [0]=> string(3) "man" [1]=> string(6) "amster" [2]=> string(5) "apple" [3]=> string(3) "ham" [4]=> string(2) "ed" }
I hope the explanation with the comments is enough.