<?php
error_reporting(-1);
mb_internal_encoding('utf-8');
 
$text = "А роза упала на лапу Азора";
$result = "палиндром";
$lText = mb_strtolower($text);
$text = str_replace(" ", "", $lText);
 
 
$length = mb_strlen($text);
$halfLength = floor($length / 2);
 
for ($i = 0; $i <= $halfLength; $i++) {
	$tx = mb_substr($text, $i, 1);
	$xt = mb_substr($text, (-1 -$i), 1);
        if ($tx == $xt) {
        	echo "Пока всё идет нормально... {$tx} соответствует {$xt}\n";
        }
        elseif ($tx != $xt) {
        	echo "Упс, нестыковочка... {$tx} не совпадает с {$xt}, это не {$result}.\n";
        	break;
        }
 
};
 
if ($tx == $xt) {
	echo "Да, эта фраза - {$result}";
}
 
 

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