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

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