3v4l.org

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<?php $prefix = (string) 1234; $id = (string) 3; $number = $prefix . str_repeat('0', 12 - strlen($prefix) - strlen($id)) . $id; $odd = true; $checksum = 0; $key = range(0, 9); for ($i = strlen($number); $i > 0; $i--) { $checksum += $key[$number[$i - 1]] * (($odd = !$odd) ? 3 : 1); } $checksum = 10 - $checksum % 10; $checksum = ($checksum == 10) ? 0 : $checksum; echo $number . $checksum;
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
1234000000039
preferences:
312.02 ms | 406 KiB | 460 Q