Re: is PHP crazy, or am I?

I must have deleted the line by accident... $trocou=true; is right below $vetor[$j+1]=$aux; would that make sense? I'm not worried about the optimization here... I want to get time results for bubblesort... and then I'm going to heap, quick, and others... It's some college homework for my girlfriend... At 00:07 14/09/01 -0500, you wrote:

function bubblesort(&$vetor,$tam) {

    $trocou=true;
    $i=$j=0;

    while($trocou)
    {
        $trocou=false;

# You set $trocou to false here, and never reset it to true # This loop will execute exactly once.

        for($j=0; $j<$tam-$i; $j++)
        {
            if($vetor[$j] > $vetor[$j+1])
            {
                $aux=$vetor[$j];
                $vetor[$j]=$vetor[$j+1];
                $vetor[$j+1]=$aux;
            }
            $i++;
        }
    }

} it's right right? No. As near as I can figure, you are incrementing $j and decrementing $i on every iteration. That would mean that even if you fixed $trocou your sort algorithm would be O(n) (Actually it's exactly 1/2 n, but that's the same as O(n) for sufficiently large n.) Alas, that can't be correct (we wish) and is not the standard bubble sort... Try this for the body: for ($i = 0; $i < $tam -1; $i++){

    for ($j = $i + 1; $j < $tam -1; $j++){
        if ($vetor[$i] < $vetor[$j]){
            $aux = $vetor[$i];
            $vetor[$i] = $vetor[$j];
            $vetor[$j] = $aux;
        }
    }

} Forget the trocou bit. so why when I print the array (with a for(;;) or with print_r) it still shows me it's not ordered... I printed it INSIDE the function... what's the thing here? I'm I nuts? -- WARNING richard@zend.com address is an endangered species -- Use ceo@l-i-e.com Wanna help me out? Like Music? Buy a CD: http://l-i-e.com/artists.htm Volunteer a little time: http://chatmusic.com/volunteer.htm