6/49 random tickets generator for analytics purposes

<?php

    function generate_new_numbers()
    {
        $numbers = array();

        // Generate 6 numbers
        for ($i = 0; $i < 6; $i++)
        {
            // Check for duplicates first
            $check = false;
            while (!$check)
            {
                $temp = mt_rand(1, 49);
                if (!in_array($temp, $numbers))
                {
                    // Then add the number in the array
                    $numbers[] = $temp;
                    $check = true;
                }
            }
        }

        return $numbers;
    }

    // Return how many numbers from
    // array $a1 exist in array $a2
    function check_numbers($a1, $a2)
    {
        $i = 0;
        foreach ($a1 as $val)
            if (in_array($val, $a2))
                $i += 1;

        return $i;
    }

    // Return how many tickets have $x winning numbers
    function winning_tickets_nr($arr, $x)
    {
        $i = 0;
        foreach ($arr as $key => $value)
            if ($value == $x)
                $i += 1;

        return $i;
    }

    // Add spaces after each 3 digits to make
    // the given number easily readable
    function format_big_nr($bigint)
    {
        $temp = '';
        $bigint = intval($bigint);

        while ($bigint > 999)
        {
            $nrtostr = strval($bigint);
            $temp .= ' ' . substr($nrtostr, strlen($nrtostr)-3, 4);
            $bigint = intval($bigint / 1000);
        }

        $bigint = $bigint . $temp;

        return $bigint;
    }

    // Generate a random winning ticket
    $winning_ticket = generate_new_numbers();

    // How many tickets to generate
    $tickets_to_gen = isset($_GET['nr']) ? intval($_GET['nr']) : 1;

    // The generated tickets
    $tickets_gened = array();

    // Generate the random tickets
    // based on $tickets_to_gen
    for ($i = 0; $i < $tickets_to_gen; $i++)
    {
        $new_nrs = generate_new_numbers();
        $tickets_gened[implode(', ', $new_nrs)] = check_numbers($new_nrs, $winning_ticket);
    }

    // Show the results
    echo 'Numar de bilete generate: '. format_big_nr($tickets_to_gen) .'<br />';
    echo 'Numar de bilete cu 3 nr. castigatoare: '. winning_tickets_nr($tickets_gened, 3) .'<br />';
    echo 'Numar de bilete cu 4 nr. castigatoare: '. winning_tickets_nr($tickets_gened, 4) .'<br />';
    echo 'Numar de bilete cu 5 nr. castigatoare: '. winning_tickets_nr($tickets_gened, 5) .'<br />';
    echo 'Numar de bilete cu 6 nr. castigatoare: '. winning_tickets_nr($tickets_gened, 6) .'<br />';

    echo '<br />Numerele extrase: '. implode(', ', $winning_ticket) .'<br />';

    // Show the winning tickets with 6 numbers
    // if there are any
    if (winning_tickets_nr($tickets_gened, 6) > 0)
    {
        echo 'Biletele cu 6 nr. castigatoare:';
        foreach ($tickets_gened as $key => $value)
            if ($value == 6)
                echo " $key ;";
    }

?>