如何在函数本身中输出函数的参数

Question

<?php


$l = 4000;

function flip($h, $t)
{

    if ($h + $t <= 29) {
        $a = mt_rand(0, 1);
        if ($a == 1) {
            flip($h + 1, $t);
        } else {
            flip($h, $t + 1);
        }

    } else {

        echo "$h,$t" . "</br>";
    }

}

$ar = array( "test");


for ($i = 0; $i <= $l; $i++) {
    array_push($ar, flip(0, 0));
}


?>

My code is supposed to give the number of tails and heads upon spinnings 30 times. And this process is done 4000 times. I want to store all the results of the 4000 times in an array using the above code. But I think the way I defined by flip is wrong. I didn't know how to store the value of the arguments of flip after it is done therefore I used an echo.

When i run this code.. for some reason it is printing out all the answers like this : http://searchr.us/testing/ip.php instead of just making an array. I have pin pointed that the way I took the vfilanl values of flip wrong. Can someone tell me the difference between echo , print and how DO i use return. When i just use return(); after echo.It gives me an error.

Please clarify my doubt on how I can output these values.

Answer 1

You should use something like this:

<?php

function flip($h, $t)
{

    if ($h + $t > 29) return $h . ',' . $t;
    $a = mt_rand(0, 1);
    return $a == 1 ? flip($h + 1, $t) : flip($h, $t + 1);

}

$ar = array( "test");

$l = 4000;
for ($i = 0; $i <= $l; ++$i) {
    array_push($ar, flip(0, 0));
}

?>

Note that echo outputs to the client.

But you want to decide what you get when you call flip, and that is done using return.