Random number

[sudeepk]

Hi, I need to generate random numbers which i have a limit of min 1 and max 7000. And in between this numbers i don't need to introduce few sets of numbers like 400 to 800 and 4600 to 5000. Please guide me.

 

I simply wrote

 

$rand = (rand(1,7000));

 

Now, how should i stop those numbers from coming up.

[cags]

After generating a number check if it's between any of the disallowed ranges, if it is then generate another number and continue until you generate one that isn't between those ranges.

[papaface]

Try:

<?php
    function in_multiarray($elem, $array)
    {
        $top = sizeof($array) - 1;
        $bottom = 0;
        while($bottom <= $top)
        {
            if($array[$bottom] == $elem)
                return true;
            else
                if(is_array($array[$bottom]))
                    if(in_multiarray($elem, ($array[$bottom])))
                        return true;
                   
            $bottom++;
        }       
        return false;
    }

$ranges = range(4600,5000);
$ranges[] = range(400,800);
$rand = rand(1,7000);
while	(in_multiarray($rand,$ranges))
$rand = rand(1,7000);
echo "yay:".$rand;
?>

[sudeepk]

Wow! I dint expect this quick reply. )

 

Thanks a lot to both of you.

 

Enlightened.

[teamatomic]

Dont use rand(), instead use arrays and array_rand.

$array1=array(range(1,4),range(10,20),range(50,58));
$nums=array_merge($array1[0],$array1[1],$array1[2]);
$key = array_rand($nums, 1);
echo $nums[$key];
echo "<br><pre>";
print_r($nums);

Another way would be to use one array for the excluded ranges and another for the entire range and do an array_unique then an array_rand on the resulting array.

 

 

HTH

Teamatomic

[sudeepk]

Now, i just got to know that i need to avoid many individual numbers too.. :|

like 46, 207, 336, 982 so on.. etc.. :|

 

i see ranges here.. how to deal with individual numbers?

 

@teamatomic

Thanks to you too..

I will learn more about it and implement it..

[papaface]

Not saying my way is the best possible way to do it, but it works.

<?php
    function in_multiarray($elem, $array)
    {
        $top = sizeof($array) - 1;
        $bottom = 0;
        while($bottom <= $top)
        {
            if($array[$bottom] == $elem)
                return true;
            else
                if(is_array($array[$bottom]))
                    if(in_multiarray($elem, ($array[$bottom])))
                        return true;
                   
            $bottom++;
        }       
        return false;
    }
   
$ranges = range(4600,5000);
$ranges[] = range(400,800);
$ranges[] = array(46, 207, 336, 982);
$rand = rand(1,7000);
while   (in_multiarray($rand,$ranges))
$rand = rand(1,7000);
echo "yay:".$rand;
?>

[sudeepk]

@papaface

sry i dint mention..

iam already using yours.

thnaks a lot

 

and i wont forget to add ur names in guidance credits in my project.

[sudeepk]

It works like a charm.

 

I have a small problem again and a last one.

 

Can i implement something like if the value of the input is zero or any rejected number by brute forcing like

 

project.php?input=4275

 

where 4275 is already banned.

 

So that it redirects to the home page

[papaface]

Not sure how you'd want that implemented in the code but it would be

if (in_multiarray($_GET['input'],$ranges)) { header('Location: banned.php'); } else { //done something }

Is that what you want?

[sudeepk]

Here i start with index page with link which generates a random link in which it has a "random number".html iframed. So finally the link looks like project.php?input=stuff/4214.html . In this link when i delete the ?input=stuff/4214.html leaving project.php as link. The iframe shows the parent website in the iframe. So here i need to do some coding where if i open project.php directly it redirects to index.php where people can start with the generated link as usual.

 

I read a php ebook today and started working. Iam a noob in php.

[ChemicalBliss]

Quite simple with an if condition, header call and exit call:

 

if(count($_GET) <= 0){
   Header('location: index.php');
   exit();
}

 

-cb-

[sudeepk]

it solves to a extent but can we do something like if the embeded iframe link doesnt have

 

?input=thing.html

 

then it redirects to index page.

[ChemicalBliss]

Same principle.

 

You can check specific array variabes like so: $array['index_name'];

 

In your case: $_GET['input'] != "thing.html"

 

-cb-