day 17

aoc_wim/aoc2023/q16.py

@@ -3,6 +3,7 @@
 https://adventofcode.com/2023/day/16
 """
 from aocd import data
+
 from aoc_wim.zgrid import ZGrid
 
 

aoc_wim/aoc2023/q17.py

@@ -0,0 +1,48 @@
+"""
+--- Day 17: Clumsy Crucible ---
+https://adventofcode.com/2023/day/17
+"""
+from aocd import data
+
+from aoc_wim.search import AStar
+from aoc_wim.zgrid import ZGrid
+
+
+class Q17AStar(AStar):
+    def __init__(self, state0, min_tail, max_tail):
+        self.min_tail = min_tail
+        self.max_tail = max_tail
+        super().__init__(state0, None)
+
+    def cost(self, current_state, next_state):
+        return grid[next_state[-1]]
+
+    def adjacent(self, state0):
+        tail, dz, z = state0
+        adj = []
+        if tail < self.max_tail and z + dz in grid:
+            adj.append((tail + 1, dz, z+dz))
+        if self.min_tail <= tail and z + dz * 1j in grid:
+            adj.append((1, dz * 1j, z + dz * 1j,))
+        if self.min_tail <= tail and z + dz * -1j in grid:
+            adj.append((1, dz * -1j, z + dz * -1j,))
+        if z == 0 and self.min_tail:
+            adj.append((1, 1j, z + 1j))
+        return adj
+
+    def target_reached(self, current_state, target):
+        tail, dz, z = current_state
+        return z == bottom_right and tail >= self.min_tail
+
+
+grid = ZGrid(data, transform=int)
+s0 = (0, 1, 0)  # state vector: tail-length, direction, position
+bottom_right = grid.bottom_right  # target
+
+astar = Q17AStar(s0, min_tail=0, max_tail=3)
+astar.run()
+print("answer_a:", astar.gscore[astar.target])
+
+bstar = Q17AStar((0, 1, 0), min_tail=4, max_tail=10)
+bstar.run()
+print("answer_b:", bstar.gscore[bstar.target])

tests/2023/17/0.txt

@@ -0,0 +1,15 @@
+2413432311323
+3215453535623
+3255245654254
+3446585845452
+4546657867536
+1438598798454
+4457876987766
+3637877979653
+4654967986887
+4564679986453
+1224686865563
+2546548887735
+4322674655533
+102
+94

tests/2023/17/1.txt

@@ -0,0 +1,7 @@
+111111111111
+999999999991
+999999999991
+999999999991
+999999999991
+-
+71