<?php
 
error_reporting(-1);
mb_internal_encoding("utf-8");
 
$text = "А роза упала на лапу Азора";
$result = "палиндром";
 
$text = mb_strtolower($text); /* переводим строку в нижний регистр */
$lenght = mb_strlen($text); /* длина исходной строки */
$symbols = ''; /* переменная под строку без пробелов */
 
/* вырежем пробельчики */
for ($i = 0; $i < $lenght; $i++) {
  $symbol = mb_substr($text, $i, 1);
  if ($symbol != " ")
    $symbols .= $symbol;
}
 
$lenght = mb_strlen($symbols); /* длина строки без пробелов */
$halfLenght = floor($lenght / 2);
 
for ($i = 0; $i <= $halfLenght; $i++) {
  if (mb_substr($symbols, $i, 1) != mb_substr($symbols, -++$i, 1) ) {
      $result = "не палиндром!";
      break;
  }
}
 
echo "Результат: {$result}\n";

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