Online PHP editor | output for mRE5J

<?php interface Kubus { public function set_sisi($s); public function luas_kubus(); public function volume_kubus(); } interface Balok { public function luas_balok($p, $l); public function volume_balok($t); } class Hitung implements Kubus, Balok{ public $p,$l,$sisi; public function set_sisi($s) { $this->sisi = $s; return $this; } public function luas_kubus() { echo "Luas Kubus = " . $this->sisi * 2 . PHP_EOL; return $this; } public function volume_kubus() { echo "Volume Kubus = " . $this->sisi * 3 . PHP_EOL; return $this; } public function luas_balok($p, $l) { $this->p = $p; $this->l = $l; echo "Luas Balok = " . $p * $l . PHP_EOL; return $this; } public function volume_balok($t) { echo "Volume Balok = " . $this->p * $this->l * $t . PHP_EOL; } } $hitung = new Hitung; echo $hitung->set_sisi(4)->luas_kubus()->volume_kubus()->luas_balok(8,4)->volume_balok(2);