Online PHP editor | output for i8WGS

<?php class MemUsage{ protected $s = null; public function start(){ $this->s = memory_get_usage(); } public function get(){ return memory_get_usage()-$this->s; } } class X{ protected $v = null; public function __construct(){ $this->v = str_repeat("a", 1024*100); } } $memUsage = new MemUsage(); $memUsage->start(); $x1 = new X(); echo $memUsage->get()."\n"; //$memUsage->start(); $x2 = new X(); echo $memUsage->get()."\n";