add day 16 part 1

day16/code.py

@@ -0,0 +1,109 @@
+import sys
+sys.path.append('../aoclib')
+
+from aoclib import Input
+import heapq
+sys.setrecursionlimit(15000)
+
+L = '<'
+U = '^'
+R = '>'
+D = 'v'
+
+EMPTY = '.'
+WALL = '#'
+START = 'S'
+END = 'E'
+
+
+class Maze:
+    def __init__(self, lines: list[list[str]]):
+        self.grid = lines
+        for y in range(len(self.grid)):
+            for x in range(len(self.grid[0])):
+                if self.grid[y][x] == START:
+                    self.s = (x, y)
+                elif self.grid[y][x] == END:
+                    self.e = (x, y)
+
+    def __str__(self):
+        grid = [r.copy() for r in self.grid]
+        return '\n'.join(''.join(row) for row in grid)
+
+    def start(self) -> tuple[int, int]:
+        return self.s
+
+    def end(self, pos: tuple[int, int]) -> bool:
+        return self.e == pos
+
+    def is_wall(self, pos) -> bool:
+        x, y = pos
+        return self.grid[y][x] == WALL
+
+
+def search(m: Maze) -> int:
+    x, y = m.start()
+    state = (x, y, 1, 0)
+
+    queue = []
+    visited = set()
+    heapq.heappush(queue, (0, state))
+    visited.add(state)
+
+    while queue:
+        cost, state = heapq.heappop(queue)
+        x, y, xd, yd = state
+
+        if m.end((x, y)):
+            return cost
+
+        options = [
+            # move forward
+            (cost+1, (x+xd, y+yd, xd, yd)),
+            # turn
+            (cost+1000, (x, y, -yd, xd)),
+            (cost+1000, (x, y, yd, -xd)),
+        ]
+
+        for opt in options:
+            cost, state = opt
+            x, y, _, _ = state
+            if m.is_wall((x, y)):
+                continue
+            if state in visited:
+                continue
+            
+            visited.add(state)
+            heapq.heappush(queue, (cost, state))
+    return -1
+       
+def solve1(lines: list[list[str]]):
+    m = Maze(lines)
+    res = search(m)
+    return res
+
+
+def solve2(lines: list[list[str]]):
+    maze = Maze(lines)
+    return ''
+
+
+if __name__ == '__main__':
+    lines = Input('input_test.txt').lines_as_lists()
+    #part 1
+    print('test part 1:', solve1(lines))
+    #part 2
+    print('test part 2:', solve2(lines))
+
+    lines = Input('input_test2.txt').lines_as_lists()
+    #part 1
+    print('test 2 part 1:', solve1(lines))
+    #part 2
+    print('test 2 part 2:', solve2(lines))
+
+    lines = Input('input.txt').lines_as_lists()
+    #part 1
+    print('part 1:', solve1(lines)) # 90460
+
+    #part 2
+    print('part 2:', solve2(lines))