🥿

y2022/p20.py

+from collections import deque
+
+
+def run(src, cycles=1, factor=1):
+    els = deque([(i, int(n) * factor) for i, n in enumerate(src)])
+    zero, = [el for el in els if el[1] == 0]
+    order = list(els)
+    for _ in range(cycles):
+        for el in order:
+            idx = els.index(el)
+            els.rotate(-idx)
+            els.popleft()
+            els.rotate(-el[1])
+            els.appendleft(el)
+    idx = els.index(zero)
+    els.rotate(-idx)
+    return sum(els[n % len(els)][1] for n in [1000, 2000, 3000])
+
+
+els = open(0).read().splitlines()
+print(run(els))
+print(run(els, cycles=10, factor=811589153))