<?php
 
 
error_reporting(-1);
mb_internal_encoding('UTF-8');
 
$text = "Аргентина манит негра";
$result = "палиндром";
$text = mb_strtolower($text);
$text = str_replace(" ", "", $text);
 
$length = mb_strlen ($text);
$halfLength = floor($length/2);
 
$length = $length - 1;
$letters = preg_split('//u', $text, null, PREG_SPLIT_NO_EMPTY);
for ($i=0; $i <= $halfLength; $i++) {
	if ($letters[$i] !== $letters[$length - $i]) {
		$result = "не палиндром";
	break;
	}
}
echo "Это {$result}";

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