<?php
 
mb_internal_encoding('utf-8');
 
$text = "Аргентина манит негра";
$result= "Палиндром";
$result2= "Не палиндром";
$text = mb_strtolower($text);
 
$text = str_replace(" ","",$text);
 
$length = mb_strlen($text);
$halfLength = floor($length/2);
for ($i=0; $i==$halfLength; $i++) {
	$o=-$i;
	$comparison1=mb_substr($text,$i,1);
    $comparison2=mb_substr($text,$o,1);
 if ($comparison1==$comparison2) {
 	echo "Результат: $result";
    } else { 
 	echo "Результат $result2";
 }}

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