<?php
declare(strict_types = 1);

define('REAL_USAGE', false);

$items = range(0, 1000000);

$t = microtime(true);
$m = memory_get_usage(REAL_USAGE);
$p = memory_get_peak_usage(REAL_USAGE);

$results = 0;

//time: 0.095, memory: 0
//foreach ($items as $i){
//    if($i % 2){
//        $results++;
//    }
//}

//time: 1.4, memory: 22Mib
//array_walk($items, function($i, $key) use(&$results){
//    if($i % 2){
//        $results++;
//    }
//});

$m1 = memory_get_usage(REAL_USAGE);
$p1 = memory_get_peak_usage(REAL_USAGE);
$t1 = microtime(true);

echo $results . PHP_EOL;

echo sprintf("Execution time: %.6f \n",$t1 - $t);
echo sprintf("Allocated memory: %d B \n", ($m1 - $m));
echo sprintf("Peaks difference: %d B \n", ($p1 - $p));