3v4l.org

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<?php $val = array(1,0,2,1,1); $subtract = 3.5; foreach($val as $key => $item){ if ($subtract > $item){ $subtract -= $item; $val[$key] = 0; } else{ $val[$key] -= $subtract; $subtract = 0; } } print_r($val);

preferences:
45.11 ms | 402 KiB | 5 Q