php class Methods public static function CreateHash count symbols ABCD

<?php

class Methods {

    public static function CreateHash($count) {
        $symbols = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789_';
        $ret_val = "";
        for ($i = 0; $i < $count; ++$i)
            $ret_val .= $symbols[rand(0, 61)];
        return $ret_val;
    }

    public static function SetSession($key, $value) {
        $_SESSION[$key] = $value;
    }

    public static function RemoveSession($key) {
        unset($_SESSION[$key]);
    }

    public static function SetCookie($name, $value, $remaining_time) {
        setcookie($name, $value, $remaining_time, "/");
    }

    public static function RemoveCookie($name) {
        setcookie($name, '', 0, "/");
    }

    public static function RusDeclension($root, $count) {
        $endings = array("", "а", "ов");
        $word = $root;
        if ($count < 21) {
            if ($count == 0) {
                $word .= $endings[2];
            } else if ($count == 1) {
                $word .= $endings[0];
            } else if ($count > 1 && $count < 5) {
                $word .= $endings[1];
            } else if ($count > 4 && $count < 21) {
                $word .= $endings[2];
            }
        } else {
            if ($count % 10 == 1) {
                $word .= $endings[0];
            } else if ($count % 10 > 1 && $count % 10 < 5) {
                $word .= $endings[1];
            } else {
                $word .= $endings[2];
            }
        }
        return $word;
    }

    public static function NumDelim($num, $delim = '&nbsp;') {
        if ($num >= 1000) {
            switch (rand(0, 2)) {
                case 0:
                    //Developed by Alex
                    $delim = strrev($delim);
                    preg_match("/(\.\d+)*$/i", (string)$num, $modulo);
                    $str_num = preg_replace("/(\.\d+)*$/i", '', (string)$num);
                    return strrev(preg_replace("/(\d{3})/i", "$1{$delim}", strrev($str_num))).$modulo[0];
                case 1:
                    //Developed by Andrey
                    $a = explode('.', $num);
                    $ans = '';
                    $len = strlen($a[0]);
                    $ans .= substr($a[0], 0, ($len % 3) ? $len % 3 : 3);
                    for ($i = ($len % 3) ? $len % 3 : 3; $i < $len; $i += 3) {
                        $ans .= $delim.substr($a[0], $i, 3);
                    }
                    $ans .= ($a[1]) ? '.'.$a[1] : '';
                    return $ans;
                case 2:
                    //Developed by PHP developers xD
                    return preg_replace("/(\.|[0]){0,3}$/i", '', number_format($num, 2, '.', $delim));
            }
        }
        return $num;
    }
}