<?php
 
error_reporting(-1);
mb_internal_encoding('utf-8');
 
$text = "это не плалиндром";
$result = 'палиндром';
 
echo ">> $text.\n";
 
$text = mb_strtolower($text);
$text = str_replace(" ","",$text);
 
$lenght = mb_strlen($text);
$halfLenght = floor($lenght/ 2);
$leftNumb = 0;
$rightNumb = -1;
 
echo "-------------------------\n";
 
for ($i = 0; $i <= $halfLenght; $i++) {
 
	$left = mb_substr($text, $leftNumb, 1);
	$right = mb_substr($text, $rightNumb, 1);
	echo "{$left} и {$right}\n";
 
	if($left == $right && $i == $halfLenght) {
 
		echo "----------------------\n";
		echo "Это $result\n";
		break;
	}
	else {
		$rightNumb--;
		$leftNumb++;
		//echo "$dvaa\n";
	}
}

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