Replace With Alphabet Position

replace-w-alphabet-position.php

<?php 

/**
 * Replace With Alphabet Position
 *
 * @author  Phan Vu Hoang <vu-hoang.phan@ekino.com>
 */

function alphabet_position(string $str) {
	$ar_pos = [];
	$str_len = strlen($str);

	for ($i=0; $i < $str_len; $i++) { 
		$char = substr($str, $i, 1);
		if (processing(strtolower($char))) {
			$ar_pos[] = processing(strtolower($char));
		}
		
	}
	
	return implode($ar_pos, ' ');
}

function processing($char) {

	$report=[]; // key => val ex. 1 => a. 2 => b
	$init = 0; //equal a
	do{
		if($init==0){
			$letter='a';
		}else{
			$letter++;
		}	

		$init++;
		$report[$letter] = $init;
	}while($letter!=='z');
	
	if (ctype_lower($char)) {
		return $report[$char];
	}
	
	return false;	
}