2024 Dec 12th

Python/2024/12/main.py

@@ -0,0 +1,45 @@
+input = open("input", 'r')
+
+# d = [line for line in input]
+# d = [[val for val in line.strip()] for line in input]
+d = {(complex(x,y)): c for y,line in enumerate(input) for x,c in enumerate(line.strip())}
+
+def run(p2=False):
+    regionPrice = []
+    s = set()
+    for point, plot in d.items():
+        if point in s: continue
+        q = [point]
+        area = 0
+        sides = set()
+
+        while q:
+            point = q.pop()
+            if point in s: continue
+            s.add(point)
+            area += 1
+
+            for dr in {1,-1,1j,-1j}:
+                npoint = point + dr
+                if npoint in d and d[npoint] == plot:
+                    q.append(npoint)
+                else:
+                    sides.add((dr, point))
+        if p2:
+            nsides = sides.copy()
+            for side in sides:
+                if side not in nsides:
+                    continue
+                sdr, spoint = side
+                for dr in {1,-1,1j,-1j} - {sdr, -sdr}:
+                    point = spoint + dr
+                    while (sdr, point) in nsides:
+                        nsides.discard((sdr,point))
+                        point = point + dr
+            sides = nsides
+        regionPrice.append(len(sides) * area)
+
+    return sum(regionPrice)
+
+print(run())
+print(run(True))