18.1

18/main.py

@@ -0,0 +1,57 @@
+from collections import deque
+
+with open("input") as f:
+    data = f.read().strip().split("\n")
+    data = list(map(lambda x: list(map(int, x.split(","))), data))
+
+
+def make_field(data, w=71, h=71):
+    field = [["."] * (w + 2) for _ in range(h + 2)]
+    for i, j in data:
+        field[i + 1][j + 1] = "#"
+    for i in range(w + 2):
+        field[0][i] = "#"
+        field[h + 1][i] = "#"
+    for i in range(h + 2):
+        field[i][0] = "#"
+        field[i][w + 1] = "#"
+    return field
+
+
+def part1(field):
+    w = len(field[0])
+    h = len(field)
+    scores = [[float("+inf")] * w for _ in range(h)]
+    scores[1][1] = 0
+    q = deque([(1, 2), (2, 1)])
+    d = [(1, 0), (0, 1), (-1, 0), (0, -1)]
+    while q:
+        i, j = q.popleft()
+        if scores[i][j] == float("+inf") and field[i][j] != "#":
+            m = min(scores[i + di][j + dj] for di, dj in d)
+            scores[i][j] = m + 1
+            for di, dj in d:
+                if (
+                    scores[i + di][j + dj] == float("+inf")
+                    and field[i + di][j + dj] != "#"
+                ):
+                    q.append((i + di, j + dj))
+
+    return scores
+
+
+def print_field(scores, field):
+    for i, row in enumerate(field):
+        for j, cell in enumerate(row):
+            if cell == "#":
+                print("#", end="")
+            elif scores[i][j] == float("+inf"):
+                print("i", end="")
+            else:
+                print(".", end="")
+        print()
+
+
+field = make_field(data[:1024])
+# print_field(part1(field), field)
+print(part1(field)[-2][-2])