Day 3: Toboggan Trajectory

Classes:

InputLine(line)

Represent a line of the input map.

Functions:

parse_input(lines)	Parse the input map given as lines.
count_trees(width, height, input_string)	Count the trees in the input_string.

class InputLine(line: str)

Represent a line of the input map.

parse_input(lines: Sequence[InputLine]) → Tuple[int, int, str]

Parse the input map given as lines.

Requires

• len(lines) > 0

• all(
      len(line) == len(lines[0])
      for line in lines
  )
  

Ensures

• result[0] * result[1] == len(result[2])

count_trees(width: int, height: int, input_string: str) → int

Count the trees in the input_string.

Requires

• width * height == len(input_string)

• re.match(r"^[.#]*", input_string)

• width > 0 and height > 0

Ensures

• result <= height / STEP_SIZE_VERTICAL