asked on

8 Unique Numbers

Hello,

I need to randomly generate 8 UNIQUE random numbers.

No number may be used more than once.

So this number is good:
53962471

This number is NOT because some numbers are duplicated:
11223344

What is the shortest/simplest way to do this?

glcummins

Not sure that this method is the simplest, but it will definitely work and is extensible in case your requirements change:

<?php
 
$uniqueNumbers = 8;
$highestValue = 9;
$lowestValue = 1;
 
$arrGeneratedNumbers = array();
 
for ($i = 0; $i<$uniqueNumbers; $i++)
{
	$foundUnique = false;
	
	while (!$foundUnique)
	{
		$newNumber = rand($lowestValue, $highestValue);
		if (!in_array($newNumber, $arrGeneratedNumbers))
		{
			$arrGeneratedNumbers[] = $newNumber;
			$foundUnique = true;
		}
	}
}
 
foreach ($arrGeneratedNumbers as $number)
{
	echo $number;
}
 
?>

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SOLUTION

glcummins

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agriesser

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spoxox

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hankknight

ASKER

I feel silly answering my own question but the ideas keep getting more complex.

One of your ideas triggered a lightening bolt in my head and I came up with this.

What do you think?

<?php
 $str = '0123456789';
 $shuffled = str_shuffle($str);
 echo substr($shuffled,-8);
?>

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glcummins

Yes, that will work, and will allow you to start with as large a data set as desired.

ASKER CERTIFIED SOLUTION

hankknight

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