Simple Palindrome Finder

palindrome.php

<?php

function pushPalindrome(&$found, $word){
    $str = strtolower($word);

    if(strrev($str) === $str){
        $found[strtolower($str)] = $word;
    }
}

function findPalindrome($str, &$found = array(), $minimumLength = 1){
    $length = strlen($str);

    if($length < $minimumLength){
        return count($found);
    }

    if($length <= $minimumLength){
        pushPalindrome($found, $str);
        return count($found);
    }

    for($i = $minimumLength; $i <= $length ; $i++){
        pushPalindrome($found, substr($str, 0, $i));
    }

    return findPalindrome(substr($str,1), $found, $minimumLength);
}


function printPalindrome($str, $minimumLength = 1){
    $result = array();

    $palindromeFound = findPalindrome(str_replace(" ", "", $str), $result, $minimumLength);

    if($palindromeFound == 0){
        printf('The Word "%s" contains no palindromes' , $str);
    }else{
        printf('The Word "%s" contains %d palindromes:' , $str, $palindromeFound);
        foreach($result as $palindromeWord){
            echo  nl2br(PHP_EOL . $palindromeWord);
        }
    }
}

printPalindrome("madam");