<?php

interface HewanInterface {
    function suara(): string;
}

class Kucing implements HewanInterface {
    function suara(): string {
        return "meong";
    }
}

class Anjing implements HewanInterface {
    function suara(): string {
        return "guk guk";
    }
}

// Kucing
$memeng = new Kucing;
echo $memeng->suara();

echo PHP_EOL;

// Anjing
$gogok = new Anjing;
echo $gogok->suara();

echo PHP_EOL;


class HewanApalah {
    private $hewan;

    public function setHewan(HewanInterface $hewan) {
        $this->hewan = $hewan;
    }

    public function suara() {
        return $this->hewan->suara();
    }
}

$apa = new HewanApalah;

$apa->setHewan($gogok);
echo $apa->suara();
echo PHP_EOL;

$apa->setHewan($memeng);
echo $apa->suara();
echo PHP_EOL;