🐝

y2022/p15.py

+import collections
+import re
+
+text = open(0).read()
+grid = {}
+match = {}
+for x, y, a, b in [[int(n) for n in re.findall(r'-?\d+', ln)] for ln in text.splitlines()]:
+    match[complex(x, y)] = complex(a, b)
+
+goal = 2000000
+bop = 4000000
+seen = set()
+count = collections.Counter()
+for aa, bb in match.items():
+    diff = bb - aa
+    reach = int(abs(diff.real) + abs(diff.imag))
+    dist = int(abs(aa.imag - goal))
+    if reach > dist:
+        df = reach - dist
+        seen |= set(range(int(aa.real - df), int(aa.real + df)))
+
+    for rot in [1j ** i for i in range(4)]:
+        for dx in range(reach):
+            dy = reach - dx
+            edgy = aa + complex(dx, dy) * rot
+            for dot in [rot, rot * 1j]:
+                bip = edgy + dot
+                if 0 <= bip.real <= bop and 0 <= bip.imag <= bop:
+                    count[bip] += 1
+
+print(len(seen))
+fin = count.most_common()[0][0]
+print(fin, int(fin.real * bop + fin.imag))