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run code in 300+ PHP versions simultaneously
<?php $count = 0; if ($handle = opendir('.')) { while (false !== ($entry = readdir($handle))) { $count++; } closedir($handle); } $f = fopen("test", "w"); while(true) { fwrite($f, "0000000000000000000000000000000000000000"); } echo $count;

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34.65 ms | 402 KiB | 5 Q