Online PHP editor | output for IV8qQ

<?php interface CounterInterface { public function getCount(); public function increment(); } class Counter implements CounterInterface { private $counter = 0; public function getCount() { return $this->counter; } public function increment() { $this->counter = $this->getCount() + 1; } } class CounterOffsetByOne extends Counter { public function getCount() { return parent::getCount() + 1; } } class DecoratedCounterOffsetByOne implements CounterInterface { private $baseCounter; public function __construct() { $this->baseCounter = new Counter; } public function getCount() { return $this->baseCounter->getCount() + 1; } public function increment() { $this->baseCounter->increment(); } } $counter = new CounterOffsetByOne; $counter->increment(); $counter->increment(); var_dump($counter->getCount()); $counter = new DecoratedCounterOffsetByOne; $counter->increment(); $counter->increment(); var_dump($counter->getCount());