Also, I don't see any actual tests verifying the output is correct. Gist of the algorithm seems to be classify numbers into buckets based on their factor of ra

Also, I don't see any actual tests verifying the output is correct. Gist of the algorithm seems to be classify numbers into buckets based on their factor of range (min, max values), then sort each bucket recursively if greater than 1000 elements or use conventional sorts before serially combining all the buckets for the result.