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import pathlib |
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2
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import re |
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3
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from typing import cast, List, Tuple |
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4
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5
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MOVE_REGEX = re.compile(r'^move (\d+) from (\d+) to (\d+)$') |
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6
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7
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8
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def parse_initial_state(state_lines): |
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9
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stack_ids = list(map(int, state_lines.pop().split())) |
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10
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stacks = {i: [] for i in sorted(stack_ids)} |
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11
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12
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def split_x(chunk_size): |
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13
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return [line[i:i + chunk_size] for i in range(0, len(line), chunk_size + 1)] |
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14
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15
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for line in reversed(state_lines): |
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16
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for create, stack in zip(split_x(3), stack_ids): |
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if create == ' ': |
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continue |
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19
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20
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stacks[stack].append(create) |
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21
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return stacks |
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22
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23
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24
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def parse_moves(lines) -> List[Tuple[int, int, int]]: |
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25
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return cast( |
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List[Tuple[int, int, int]], |
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[ |
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28
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tuple(map(int, re.match(MOVE_REGEX, line).groups())) |
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for line in lines |
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30
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] |
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31
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) |
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32
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33
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34
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def parse(lines): |
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35
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split_idx = lines.index('') |
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36
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return ( |
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37
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parse_initial_state(lines[:split_idx]), |
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38
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parse_moves(lines[split_idx + 1:]) |
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39
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) |
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40
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41
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42
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def solve(init_state, moves, pick_group): |
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43
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state = {k: v[:] for k, v in init_state.items()} |
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44
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45
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for n, from_, to in moves: |
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46
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pick = [state[from_].pop() for _ in range(n)] |
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47
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if pick_group: |
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48
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pick.reverse() |
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49
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50
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state[to].extend(pick) |
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51
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return state |
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52
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53
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54
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def collect_output(state): |
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55
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return ''.join(g[-1][1] for g in state.values()) |
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56
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57
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58
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def main(): |
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59
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content = pathlib.Path('./input.txt').read_text() |
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60
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initial_state, moves = parse(content.splitlines()) |
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61
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62
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print("Part 1:", collect_output(solve(initial_state, moves, False))) |
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63
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print("Part 2:", collect_output(solve(initial_state, moves, True))) |
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64
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65
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66
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if __name__ == '__main__': |
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67
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main() |
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68
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Sigmanificient /
aoc
