CODEWITHSUNDEEP
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Cydonia7
Cydonia7

Reputation: 3826

Random integer with conditions

I have a PHP script where I have an array of integers, let's say $forbidden.

I want to get a random integer from 1 to 400 that is not in $forbidden.

Of course, I don't want any loop which breaks when rand gives a working result. I'd like something more effective.

How do you do this ?

Upvotes: 5

Views: 256

Answers (2)

Ed Heal
Ed Heal

Reputation: 59997

Produce an array of the allowed numbers. Find out the number in this array. Select one of those randomly.

Upvotes: 0

Madara's Ghost
Madara's Ghost

Reputation: 174957

Place all forbidden numbers in an array, and use array_diff from range(1,400). You'll get an array of allowed numbers, pick a random one with array_rand().

<?php

$forbidden = array(2, 3, 6, 8);
$complete = range(1,10);
$allowed = array_diff($complete, $forbidden);

echo $allowed[array_rand($allowed)];

This way you're removing the excluded numbers from the selection set, and nullifying the need for a loop :)

Upvotes: 10

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