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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 ? 3 : 1); $odd = !$odd; } $checksum = 10 - $checksum % 10; $checksum = ($checksum == 10) ? 0 : $checksum; echo $number . $checksum;
Output for 5.3.4 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.7 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.10, 7.2.0 - 7.2.33, 7.3.12 - 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 - 8.3.7
1234000000039
preferences:
186.37 ms | 405 KiB | 258 Q