3v4l.org

run code in 300+ PHP versions simultaneously
<?php $i = 0; $k = 1; $count = 1; while($count++ < 7) { echo debug_print_backtrace()."no backtrace at all\n"; $boof = $k; $k = $i + $k; $i = $boof; }

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28.84 ms | 404 KiB | 5 Q