Stochastik-Frage

<?php

	function createSet($low,$hi,$count,&$array) {
		while (true) {
			$r = rand($low, $hi);
			if(in_array($r, $array))
				createSet($low,$hi,$count,$array);
			else
				$array = $r;
			if(count($array) == $count)
				return true;
		}
	}
	
	function createCollection($low,$hi) {
		$a = array();
		for ($i=$low; $i <= $hi; $i++) { 
			$a[$i] = false;
		}
		return $a;
	}
	
	function collectionComplete(&$coll) {
		foreach ($coll as $key => $value) {
			if(!$value)
				return false;
		}
		return true;
	}
	
	function mergePack(&$collection,$pack) {
		$added = 0;
		foreach ($pack as $key) {
			if($collection[$key])
				continue;
			$collection[$key] = true;
			$added++;
		}
		return $added;
	}
	
	function collectionCount(&$collection) {
		$c = 0;
		foreach ($collection as $key => $value) {
			if($value)
				$c++;
		}
		return $c;
	}

	function mean(&$arr) {
		$c = 0;
		foreach ($arr as $value) {
			$c += $value;
		}
		return $c / count($arr);
	}

	$coll = createCollection(1,639);
	$packs = 0;
	$round = 1;

	while (!collectionComplete($coll)) {
		$pack = array();
		createSet(1,639,5,$pack);
		$ad = mergePack($coll,$pack);
		echo $round."\t".$ad."\t".collectionCount($coll)."\n";  
		$round++;
	}
	
?>