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-rw-r--r--12_2024.py54
1 files changed, 54 insertions, 0 deletions
diff --git a/12_2024.py b/12_2024.py
new file mode 100644
index 0000000..072603d
--- /dev/null
+++ b/12_2024.py
@@ -0,0 +1,54 @@
+from collections import deque
+
+input = "data/12_2024.txt"
+data = open(input).read().strip()
+lines = data.split("\n")
+rows = len(lines)
+cols = len(lines[0])
+p1, p2, vis = 0, 0, set()
+dirs = [(-1, 0), (0, 1), (1, 0), (0, -1)]
+
+for r in range(rows):
+ for c in range(cols):
+ if (r, c) in vis:
+ continue
+ q, dic = deque([(r, c)]), dict()
+ area, perim = 0, 0
+ while q:
+ r2, c2 = q.popleft()
+ if (r2, c2) in vis:
+ continue
+ vis.add((r2, c2))
+ area += 1
+ for dr, dc in dirs:
+ rr = r2 + dr
+ cc = c2 + dc
+ if 0 <= rr < rows and 0 <= cc < cols and lines[rr][cc] == lines[r2][c2]:
+ q.append((rr, cc))
+ else:
+ perim += 1
+ if (dr, dc) not in dic:
+ dic[(dr, dc)] = set()
+ dic[(dr, dc)].add((r2, c2))
+ sides = 0
+ for k, vs in dic.items():
+ vis_dic = set()
+ for pr, pc in vs:
+ if (pr, pc) not in vis_dic:
+ sides += 1
+ q = deque([(pr, pc)])
+ while q:
+ r2, c2 = q.popleft()
+ if (r2, c2) in vis_dic:
+ continue
+ vis_dic.add((r2, c2))
+ for dr, dc in dirs:
+ rr, cc = r2 + dr, c2 + dc
+ if (rr, cc) in vs:
+ q.append((rr, cc))
+ p1 += area * perim
+ p2 += area * sides
+
+
+print(p1)
+print(p2)