Reimplement day 5 with iterators.
Reimplement day 5 with iterators.

bertptrs/adventofcode,bertptrs/adventofcode,bertptrs/adventofcode,bertptrs/adventofcode,bertptrs/adventofcode,bertptrs/adventofcode,bertptrs/adventofcode,bertptrs/adventofcode,bertptrs/adventofcode,bertptrs/adventofcode,bertptrs/adventofcode,bertptrs/adventofcode,bertptrs/adventofcode,bertptrs/adventofcode,bertptrs/adventofcode,bertptrs/adventofcode