public static function encode($s, $t)
{
if (!$t->root) {
return;
}
// Encode the tree first.
$allBits = Huffman::encodeTree($t);
for ($i = 0; $i < strlen($s); ++$i) {
$c = $s[$i];
$current = $t->leaves[$c];
$bits = array();
while (true) {
$parent = $current->parent;
if (!$parent) {
break;
}
if ($current === $parent->left) {
array_push($bits, 0);
} else {
array_push($bits, 1);
}
$current = $parent;
}
$allBits = array_merge($allBits, array_reverse($bits));
}
return $allBits;
}
