|
| 1 | +import sys |
| 2 | + |
| 3 | +data = open(sys.argv[1]).read().strip() |
| 4 | +groups = data.split('\n\n') |
| 5 | + |
| 6 | +grid = [list(row) for row in groups[0].split('\n')] |
| 7 | + |
| 8 | +moves = list(''.join(groups[1].split('\n'))) |
| 9 | + |
| 10 | +ry, rx = 0, 0 |
| 11 | +for y, row in enumerate(grid): |
| 12 | + for x, c in enumerate(row): |
| 13 | + if c == '@': |
| 14 | + ry, rx = y, x |
| 15 | + |
| 16 | +for move in moves: |
| 17 | + match move: |
| 18 | + case '>': |
| 19 | + px = rx + 1 |
| 20 | + while grid[ry][px] != '.' and grid[ry][px] != '#': |
| 21 | + px += 1 |
| 22 | + if grid[ry][px] == '.': |
| 23 | + for i in range(px, rx, -1): |
| 24 | + grid[ry][i] = grid[ry][i-1] |
| 25 | + grid[ry][i-1] = '.' |
| 26 | + rx += 1 |
| 27 | + case '<': |
| 28 | + px = rx - 1 |
| 29 | + while grid[ry][px] != '.' and grid[ry][px] != '#': |
| 30 | + px -= 1 |
| 31 | + if grid[ry][px] == '.': |
| 32 | + for i in range(px, rx): |
| 33 | + grid[ry][i] = grid[ry][i+1] |
| 34 | + grid[ry][i+1] = '.' |
| 35 | + rx -= 1 |
| 36 | + case '^': |
| 37 | + py = ry - 1 |
| 38 | + while grid[py][rx] != '.' and grid[py][rx] != '#': |
| 39 | + py -= 1 |
| 40 | + if grid[py][rx] == '.': |
| 41 | + for i in range(py, ry): |
| 42 | + grid[i][rx] = grid[i+1][rx] |
| 43 | + grid[i+1][rx] = '.' |
| 44 | + ry -= 1 |
| 45 | + case 'v': |
| 46 | + py = ry + 1 |
| 47 | + while grid[py][rx] != '.' and grid[py][rx] != '#': |
| 48 | + py += 1 |
| 49 | + if grid[py][rx] == '.': |
| 50 | + for i in range(py, ry, -1): |
| 51 | + grid[i][rx] = grid[i-1][rx] |
| 52 | + grid[i-1][rx] = '.' |
| 53 | + ry += 1 |
| 54 | + |
| 55 | +ans = 0 |
| 56 | +for y, row in enumerate(grid): |
| 57 | + for x, c in enumerate(row): |
| 58 | + if c == 'O': |
| 59 | + ans += 100*y + x |
| 60 | +print(ans) |
| 61 | + |
| 62 | +grid = [list(row) for row in groups[0].split('\n')] |
| 63 | +grid2 = [] |
| 64 | + |
| 65 | +for y, row in enumerate(grid): |
| 66 | + row2 = [] |
| 67 | + for x, c in enumerate(row): |
| 68 | + match c: |
| 69 | + case '#': |
| 70 | + row2.extend(['#', '#']) |
| 71 | + case 'O': |
| 72 | + row2.extend(['[', ']']) |
| 73 | + case '.': |
| 74 | + grid[y][x] = '..' |
| 75 | + row2.extend(['.', '.']) |
| 76 | + case '@': |
| 77 | + row2.extend(['@', '.']) |
| 78 | + grid2.append(row2) |
| 79 | + |
| 80 | +grid = grid2 |
| 81 | + |
| 82 | +ry, rx = 0, 0 |
| 83 | +for y, row in enumerate(grid): |
| 84 | + for x, c in enumerate(row): |
| 85 | + if c == '@': |
| 86 | + ry, rx = y, x |
| 87 | + |
| 88 | +for move_idx, move in enumerate(moves): |
| 89 | + match move: |
| 90 | + case '>': |
| 91 | + px = rx + 1 |
| 92 | + while grid[ry][px] != '.' and grid[ry][px] != '#': |
| 93 | + px += 1 |
| 94 | + if grid[ry][px] == '.': |
| 95 | + for i in range(px, rx, -1): |
| 96 | + grid[ry][i] = grid[ry][i-1] |
| 97 | + grid[ry][i-1] = '.' |
| 98 | + rx += 1 |
| 99 | + case '<': |
| 100 | + px = rx - 1 |
| 101 | + while grid[ry][px] != '.' and grid[ry][px] != '#': |
| 102 | + px -= 1 |
| 103 | + if grid[ry][px] == '.': |
| 104 | + for i in range(px, rx): |
| 105 | + grid[ry][i] = grid[ry][i+1] |
| 106 | + grid[ry][i+1] = '.' |
| 107 | + rx -= 1 |
| 108 | + case '^': |
| 109 | + ny = ry - 1 |
| 110 | + next_cell = grid[ny][rx] |
| 111 | + if next_cell == '.': |
| 112 | + grid[ny][rx] = grid[ry][rx] |
| 113 | + grid[ry][rx] = '.' |
| 114 | + ry -= 1 |
| 115 | + elif next_cell in '[]': |
| 116 | + frontier = [] |
| 117 | + queue = [(ny, rx), (ny, rx + {'[': 1, ']': -1}[next_cell])] |
| 118 | + seen = set([(ry, rx)] + queue) |
| 119 | + while queue: |
| 120 | + cury, curx = queue.pop(0) |
| 121 | + nexty = cury - 1 |
| 122 | + if grid[nexty][curx] in '[]' and (nexty, curx) not in seen: |
| 123 | + queue.append((nexty, curx)) |
| 124 | + seen.add((nexty, curx)) |
| 125 | + nbr = (nexty, curx+{'[': 1, ']': -1}[grid[nexty][curx]]) |
| 126 | + queue.append(nbr) |
| 127 | + seen.add(nbr) |
| 128 | + else: |
| 129 | + frontier.append((cury, curx)) |
| 130 | + for y, x in frontier: |
| 131 | + if grid[y-1][x] == '#': |
| 132 | + break |
| 133 | + else: |
| 134 | + seen = sorted(seen) |
| 135 | + for y, x in seen: |
| 136 | + grid[y-1][x], grid[y][x] = grid[y][x], '.' |
| 137 | + ry -= 1 |
| 138 | + |
| 139 | + case 'v': |
| 140 | + ny = ry + 1 |
| 141 | + next_cell = grid[ny][rx] |
| 142 | + if next_cell == '.': |
| 143 | + grid[ny][rx] = grid[ry][rx] |
| 144 | + grid[ry][rx] = '.' |
| 145 | + ry += 1 |
| 146 | + elif next_cell in '[]': |
| 147 | + frontier = [] |
| 148 | + queue = [(ny, rx), (ny, rx + {'[': 1, ']': -1}[next_cell])] |
| 149 | + seen = set([(ry, rx)] + queue) |
| 150 | + while queue: |
| 151 | + cury, curx = queue.pop(0) |
| 152 | + nexty = cury + 1 |
| 153 | + if grid[nexty][curx] in '[]' and (nexty, curx) not in seen: |
| 154 | + queue.append((nexty, curx)) |
| 155 | + seen.add((nexty, curx)) |
| 156 | + nbr = (nexty, curx+{'[': 1, ']': -1}[grid[nexty][curx]]) |
| 157 | + queue.append(nbr) |
| 158 | + seen.add(nbr) |
| 159 | + else: |
| 160 | + frontier.append((cury, curx)) |
| 161 | + frontier = sorted(frontier) |
| 162 | + for y, x in frontier: |
| 163 | + if grid[y+1][x] == '#': |
| 164 | + break |
| 165 | + else: |
| 166 | + seen = sorted(seen, reverse=True) |
| 167 | + for y, x in seen: |
| 168 | + grid[y+1][x], grid[y][x] = grid[y][x], '.' |
| 169 | + ry += 1 |
| 170 | + |
| 171 | +ans2 = 0 |
| 172 | +for y, row in enumerate(grid): |
| 173 | + for x, c in enumerate(row): |
| 174 | + if c == '[': |
| 175 | + ans2 += 100*y + x |
| 176 | +print(ans2) |
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