generate an actual unique number rand()

[Anon]

Hi,

I'm modifying my php quiz engine to make it randomize questions. (www.techexams.net)

I'm using this code:

$number = rand(1, 25);

This results in some of the questions getting a duplicate id. Is there a simple way to 'give out' a particular number once?

For example:
if the first question (read from an xml file) gets number ID 6, that number should not be assigned/generated again, untill 1 - 25 are all 'taken'...

[ericr23]

If you know the number of questions, you could create of an array of equal length, and upon generation of a random number check the array to see if the number has been generated before, if it has generate another one, if it has not been used insert it into the array so it will not be used again.

• Eric

[Anon]

That sounds like the solution! Thanks. I do know the number of questions by counting specific 'tags' in the xml file.

I know some PHP, but I'm not experienced with arrays... can you give an example of how to define the array and insert values in it and how to check if it's already in the array.

Thanks anyway for your help so far.