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<?php function bcdechex($dec) { $last = bcmod($dec, 16); $remain = bcdiv(bcsub($dec, $last), 16); if($remain == 0) { return dechex($last); } else { return bcdechex($remain).dechex($last); } } print bcdechex(319259235818);

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66.45 ms | 402 KiB | 5 Q