<?php

// Require (n) unique characters in a string
// Modification of a function below which ads some flexibility in how many unique characters are required in a given string.

$pass = '123456' ; // true
$pass = '111222' ; // false

req_unique($pass,3);

function req_unique($string,$unique=3) {
    if ( count(count_chars($string,1)) < $unique) {
        echo 'false';
    }else{
        echo 'true';
    }
}

?>