<?php
 
$text = "А роза упала на лапу азора";
$result = "палиндром";
 
$text = mb_strtolower($text);
 
//Убираем пробелы
$text = str_replace (" ", "", $text);
 
$textLenth = mb_strlen($text);
$halfLenth = floor($textLenth/2);
 
//Cравниваем голову и хвост
for ($i = 0; $i < $halfLenth; $i++) {
    $head = mb_substr ($text, $i, 1);
    $tale = mb_substr ($text, -$i-1, 1);
    if ($head != $tale) {
       $result = "не палиндром";
       break;
    }
}
 
echo $result;
 
?>

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