The rust NonZeroU64 solution has a subtle 'bug' that happens not to matter. The function fn get_optional_non_zero(n: u64) -> Option<NonZeroU64> l

The rust NonZeroU64 solution has a subtle 'bug' that happens not to matter. The function fn get_optional_non_zero(n: u64) -> Option<NonZeroU64> let i = n & 0xFF; if i == MAGIC { None } else { NonZeroU64::new(i) } } Actually returns None for n = 0 or n is any multiple of 256. The resulting usage in the sum still yields the same result, because skipping zeros in an addition doesn't matter, but it is a subtle difference between this get-function compared to all of the others. It also doubles the number of None cases the code needs to handle.