<?php
 
error_reporting(-1);
mb_internal_encoding('utf-8');
 
$text = "А роза упала на лапу Азора";
$text = mb_strtolower(str_replace(' ', '', $text));
$result = 'палиндром';
 
$length = mb_strlen($text);
$halfLength = floor($length / 2);
 
 
for ($i = 0, $d = 1; $i <= $halfLength; $i++, $d++)
{
	if (mb_substr($text, $i, 1) != mb_substr($text, -$d, 1)) {
		$result = 'не палиндром';
	}
}
 
echo "Результат: {$result}\n";

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