<?php
error_reporting(-1);
mb_internal_encoding('utf-8');
 
$string = " нт афр  р а тн";
 
$string = mb_strtolower($string);
$string = str_replace(" ", "", $string);
 
echo "$string\n";
 
$length = floor((mb_strlen($string))/2);
 
echo "$length\n";
 
for ($i = 1; $i < $length+1; $i++) {
	echo mb_substr($string, $i-1, 1), " - ", mb_substr($string, -$i, 1), "\n";
	if (mb_substr($string, $i-1, 1) == (mb_substr($string, -$i, 1))) {
		$result = "палиндром"; 
	} else {
		$result = "не палиндром";
		break;
	}
 
}
 
echo $result;
 

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