function S_box(&$temp_B)
{
global $box_S;
$m = $n = 0;
for ($j = 0; $j < 8; $j++) {
$m = $temp_B[$j][0] * 2 + $temp_B[$j][5];
$n = $temp_B[$j][1] * 2 * 2 * 2 + $temp_B[$j][2] * 2 * 2 + $temp_B[$j][3] * 2 + $temp_B[$j][4];
$temp_B[$j] = BinToArray(DecToBin($box_S[$j][$m][$n]));
}
}
<?php
/**
* Write a string function DecToBin(N) that returns a string containing the binary representation of a
* nonnegative integer N. The string consists of characters "0", "1" and does not contain leading zeros
* (except for the representation of zero number). Using this function, output binary representations of
* five given integers.
*/
include 'helper.php';
function DecToBin($N)
{
echo decbin($N) . '<br/>';
}
DecToBin(65535);
DecToBin(255);
DecToBin(127);