<?php
error_reporting(-1);
mb_internal_encoding('utf-8');

$text = "к роза упала на лапу Азора";
$result = "палиндром";
$negativeResult = "не палиндром";

$text = mb_strtolower($text);
$text = str_replace(" ", "", $text);

$length = floor(mb_strlen($text) / 2);
$from1 = 0;
$from2 = -1;

for ($i = 0; $i <= $length; $i ++) {
	
	$letter1 = mb_substr($text, $from1, 1);
	$letter2 = mb_substr($text, $from2, 1);

	if ($letter1 == $letter2) {
		echo "$letter1 - $letter2 \n";
	$from1 ++;
	$from2 --;
	
	} else{
		echo "$letter1 - $letter2 \n\n$negativeResult";
		exit;
	}
	}

echo "$result";