Question

i wrote a php script to generate random values between 1 and 99999999999999999999 (that’s 20 9’s).

The script is like this:

$maxq=20;
for($i=1;$i<=$maxq;$i++) {
    $min=pow(10,$i);
    $max=(pow(10,$i)*10)-1;
    echo $min."<br>";
    echo $max."<br>";
    echo mt_rand($min,$max)."<br>----<br>";
}

but after 10 digit, php generates scientific notations like 1.0E+19 and the random numbers generated are a mess.

I guess think is because of my hardware imitations (OS: Win XP 32 bit).

What can i do to over come this? any help?

Thanks.

Answer 1

You could generate n random digits and concatenate them into one large string.

function randomDigits($numDigits) {
    if ($numDigits <= 0) {
        return '';
    }

    return mt_rand(0, 9) . randomDigits($numDigits - 1);
}

// Or an iterative approach
function randomDigitsLame($numDigits) {
    $digits = '';

    for ($i = 0; $i < $numDigits; ++$i) {
        $digits .= mt_rand(0, 9);
    }

    return $digits;
}

$maxq = 20;

for ($i = 1; $i <= $maxq; $i++) {
    echo $i . "<br>\n";
    echo randomDigits($i) . "<br>\n----<br>\n";
}