<?php
 
error_reporting(-1);
 
mb_internal_encoding("utf-8");
 
$text = "Сеньор-помидор пишет безошибочный код";
 
 
$result = "палиндром";
 
$text = str_replace(' ', '', mb_strtolower($text));
 
$length = mb_strlen($text);
$halfLength = floor($length / 2);
$letters = preg_split('//u', $text);
 
 
for ($i = 0; $i <= $halfLength; $i++) {
        if ($letters[$length - $i + 1] == $letters[$i])
                continue;
        else $result = "Не палиндром";
}
 
echo $result;
 

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