Palindrome checker class

palindrome_via_array.php

<?php // https://www.testdome.com/questions/php/palindrome/7320?questionIds=7320,11840&generatorId=30&type=fromtest&testDifficulty=Easy
class Palindrome {
    public static function isPalindrome($word) {
        $word = str_split(strtolower($word));
        for($i = 0; $i < ceil(count($word)/2); $i++) {
            $leftChar = $word[$i];
            $rightChar = $word[count($word)-$i-1];
            if($leftChar !== $rightChar) {
                return FALSE;
            }
        }
        return TRUE;
    }
}

echo Palindrome::isPalindrome('Deleveled');

palindrome_via_strrev.php

<?php // https://www.testdome.com/questions/php/palindrome/7320?questionIds=7320,11840&generatorId=30&type=fromtest&testDifficulty=Easy
class Palindrome
{
    public static function isPalindrome($word) {
        $word = strtolower($word);
        return $word == strrev($word);
    }
}

echo Palindrome::isPalindrome('Deleveled');

palindrome_via_substr.php

<?php // https://www.testdome.com/questions/php/palindrome/7320?questionIds=7320,11840&generatorId=30&type=fromtest&testDifficulty=Easy
class Palindrome {
    public static function isPalindrome($word) {
        $word = strtolower($word);
        for($i = 0; $i < ceil(strlen($word)/2); $i++) {
            $leftChar = substr($word, $i, 1);
            $rightChar = substr($word, -($i+1), 1);
            if($leftChar !== $rightChar) {
                return FALSE;
            }
        }
        return TRUE;
    }
}

echo Palindrome::isPalindrome('Deleveled');