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.

A generator is a program that produces test data and expected results for a challenge. Each time a solution is checked, the generator runs fresh - producing unique, unpredictable input.

Custom generators let you challenge other participants' solutions with your own test cases. If someone's solution fails on your generator's input, it exposes weaknesses in their approach. Writing good generators requires deep understanding of the problem - you need to craft edge cases, stress tests, and tricky inputs that push solutions to their limits.

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