Verify given string is palindrome or not with rearrange form?

Many interviewer ask question “How would you verify given string is palindrome or not in the PHP?”

It is very simple!

<?php
function checkPalindrome($s): bool
{
    $r = strrev($s); // revers the string
    return ($s == $r);
}
$input = 'madam';
$output = checkPalindrome($input);
echo ($output) ? 'Given string is palindrome' : 'Given string is not palindrome';

What if interviewer ask “Check given string is palindrome or not after rearrangement of string character?”

Need to think out of the box & Rub the brain!

<?php
function checkPalindrome($s): bool
{
    $break = str_split($s); // Convert string to array
    $countChar = array_count_values($break); // Count of character 
    $oddChar = [];
    foreach ($countChar as $k => $v) {
        $check = $v % 2; // Check odd or even 
        if ($check) {
            $oddChar[] = $k;
        }
    }
// Odd character count more than one treat as non palindrome string
   if(count($oddChar) > 1){
     return false;
   }
return true;
}

$output = checkPalindrome('madam');

echo ($output) ? 'Given string is palindrome' : 'Given string is not palindrome';

Logic

“Given string each character count should not odd number more than one time otherwise given string never be palindrome string.”