<?php
error_reporting(-1);
mb_internal_encoding('utf-8');
 
$text = "А роза упала на лапу Азора";
$result = "палиндром";
 
$from = [' ' => ''];
$text = strtr($text, $from);
$text = mb_strtolower($text);
 
$length = mb_strlen($text);
$halfLenght = floor($length / 2);
 
for ($i = 0; $i < $halfLenght; $i++) {
	$k = ($i + 1) * -1;
	if (mb_substr($text, $i, 1) != mb_substr($text, $k, 1)){
		$result = "не палиндром";
		break;
	}
}
 
echo "Результат: {$result}\n";

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