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<?php ob_start(); $time = microtime(1); $i = 0; while ($i++ < 10000) echo'aaaaaaa'.'aaaaaaa'.'aaaaaaa'.'aaaaaaa'; $end = microtime(1); ob_end_clean(); echo "period took ".$end-$time; ob_start(); $time = microtime(1); $i = 0; while ($i++ < 10000) echo'aaaaaaa','aaaaaaa','aaaaaaa','aaaaaaa'; $end = microtime(1); ob_end_clean(); echo "comma took ".$end-$time;

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