Online PHP editor | refs for vQAZj

<?php $chars = [ 'a' => 'c', 'b' => 'd', 'c' => 'a', 'd' => 'e', 'e' => 'b', ]; $original = 'acdcxx'; // Encrypt $encrypted = ''; for ($i = 0; $i < strlen($original); $i++) { // If we find the character in our mapping array, use the mapped character. // If not, let's use the original character. $encrypted .= array_key_exists($original[$i], $chars) ? $chars[$original[$i]] : $original[$i]; } print_r($encrypted); // Decrypt $decrypted = ''; for ($i = 0; $i < strlen($encrypted); $i++) { // Find the correct key $key = array_search($encrypted[$i], $chars); // If the character existed, use the key. // If not, use the original character. $decrypted .= $key !== false ? $key : $encrypted[$i]; } echo PHP_EOL; print_r($decrypted);