Format integers Sergey Svistunov

Compute a checksum over the decimal representations of binary integers as fast as possible.

Input: 250 000 000 uint32 values in little-endian binary on STDIN (4 bytes each).

Output: A uint64 checksum computed as:

CRC = sum of number_crc(n) for each n

where number_crc(n) converts n to its decimal string and sums ascii(digit) * position over each digit (0-indexed from the left).

Example: For n = 42, the decimal string is "42", so number_crc(42) = ascii('4') * 0 + ascii('2') * 1 = 52 * 0 + 50 * 1 = 50.

Back to listApr 27, 2026 18:20Victor MerckléVictor MerckléError
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Apr 27, 2026 18:210140,464,8610118,755,0002,514,944Exit with code 1: probe_v=input_size_1 stdin_regular=1 st_size=1000000000 errno=0 probe_v=input_size_1 stdin_regular=1 st_size=1000000000 bytes_read=1000000000 read_calls=240 eof_seen=1 elapsed_ms=116 first_read_ms=1 max_read_ms=1 mb_per_s_x1000=862068...stderr