Slightly nicer day parsing.
Slightly nicer day parsing.

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