11

11/11.py

@@ -0,0 +1,77 @@
+from math import prod
+
+def make_monkeys():
+    monkeys = {
+            0: [
+                [63, 84, 80, 83, 84, 53, 88, 72],
+                lambda x: x*11,
+                lambda x: x%13==0,
+                4, 7],
+            1: [
+                [67, 56, 92, 88, 84],
+                lambda x: x+4,
+                lambda x: x%11==0,
+                5, 3],
+            2: [
+                [52],
+                lambda x: x*x,
+                lambda x: x%2==0,
+                3, 1],
+            3: [
+                [59, 53, 60, 92, 69, 72],
+                lambda x: x+2,
+                lambda x: x%5==0,
+                5, 6],
+            4: [
+                [61, 52, 55, 61],
+                lambda x: x+3,
+                lambda x: x%7==0,
+                7, 2],
+            5: [
+                [79, 53],
+                lambda x: x+1,
+                lambda x: x%3==0,
+                0, 6],
+            6: [
+                [59, 86, 67, 95, 92, 77, 91],
+                lambda x: x+5,
+                lambda x: x%19==0,
+                4, 0],
+            7: [
+                [58, 83, 89],
+                lambda x: x*19,
+                lambda x: x%17==0,
+                2, 1],
+            }
+    return monkeys
+
+def reduce_worry(item):
+    return item//3
+
+def turn(monkey, i, monkey_business, reduce_worry=lambda x: x):
+    items, inspect, test, left, right = monkey
+    while items:
+        item = items.pop(0)
+        item = inspect(item)
+        monkey_business[i] += 1
+        item = reduce_worry(item)
+        if test(item):
+            monkeys[left][0].append(item)
+        else:
+            monkeys[right][0].append(item)
+
+def make_turns(n, reduce_worry=lambda x: x):
+    global monkeys
+    monkeys = make_monkeys()
+    monkey_business = {i:0 for i in range(8)}
+    for _ in range(n):
+        for i in range(8):
+            turn(monkeys[i], i, monkey_business, reduce_worry)
+    return prod(sorted(monkey_business.values())[-2:])
+
+print(make_turns(20, reduce_worry))
+
+mods = [13, 11, 2, 5, 7, 3, 19, 17]
+M = prod(mods)
+
+print(make_turns(10_000, lambda x: x%M))

11/input

@@ -0,0 +1,55 @@
+Monkey 0:
+  Starting items: 63, 84, 80, 83, 84, 53, 88, 72
+  Operation: new = old * 11
+  Test: divisible by 13
+    If true: throw to monkey 4
+    If false: throw to monkey 7
+
+Monkey 1:
+  Starting items: 67, 56, 92, 88, 84
+  Operation: new = old + 4
+  Test: divisible by 11
+    If true: throw to monkey 5
+    If false: throw to monkey 3
+
+Monkey 2:
+  Starting items: 52
+  Operation: new = old * old
+  Test: divisible by 2
+    If true: throw to monkey 3
+    If false: throw to monkey 1
+
+Monkey 3:
+  Starting items: 59, 53, 60, 92, 69, 72
+  Operation: new = old + 2
+  Test: divisible by 5
+    If true: throw to monkey 5
+    If false: throw to monkey 6
+
+Monkey 4:
+  Starting items: 61, 52, 55, 61
+  Operation: new = old + 3
+  Test: divisible by 7
+    If true: throw to monkey 7
+    If false: throw to monkey 2
+
+Monkey 5:
+  Starting items: 79, 53
+  Operation: new = old + 1
+  Test: divisible by 3
+    If true: throw to monkey 0
+    If false: throw to monkey 6
+
+Monkey 6:
+  Starting items: 59, 86, 67, 95, 92, 77, 91
+  Operation: new = old + 5
+  Test: divisible by 19
+    If true: throw to monkey 4
+    If false: throw to monkey 0
+
+Monkey 7:
+  Starting items: 58, 83, 89
+  Operation: new = old * 19
+  Test: divisible by 17
+    If true: throw to monkey 2
+    If false: throw to monkey 1