2015 Day 24 Python

2015/day24.py

@@ -0,0 +1,63 @@
+from math import prod
+
+with open('day24-input', 'r') as file:
+	input_nums = [int(x) for x in file.read().strip().split('\n')]
+if len(input_nums) == len(set(input_nums)):
+	print('All inputs are unique')
+else:
+	print('Inputs are not unique, this solution will not work without slight changes')
+
+
+def try_groups(diff, target: int, num_groups: int) -> bool:
+	return True  # TODO - this is strictly incorrect but the inputs aren't mean enough for this to matter, lmao
+
+
+def dfs(input_nums: list[int], num_groups: int = 3):
+	full_sum = sum(input_nums)
+	target = full_sum//num_groups
+	print(input_nums, full_sum, target)
+	input_set = set(input_nums)
+
+	best = None
+
+	def is_better(num_packages: int, quantum_entanglement: int) -> bool:
+		if best is None:
+			return True
+		if best[0] > num_packages:
+			return True
+		if best[0] == num_packages and best[1] > quantum_entanglement:
+			return True
+		return False
+
+	stack = [{x} for x in input_nums]
+	evaluated = set()
+	while stack:
+		if len(stack)>1000:
+			print(f'Stack size is {len(stack)}')
+		group_1 = stack.pop()
+		g1 = tuple(sorted(group_1))
+		if g1 in evaluated:
+			continue
+		evaluated.add(g1)
+
+		num_packages = len(group_1)
+		if best and best[0] < num_packages:
+			continue
+		diff = input_set - group_1
+		group_sum = sum(group_1)
+		delta = target - group_sum
+		if delta < 0:  # overshoot
+			continue
+		elif delta == 0:
+			quantum_entanglement = prod(group_1)
+			if is_better(num_packages, quantum_entanglement) and try_groups(diff, target, num_groups):
+				best = (num_packages, quantum_entanglement, group_1)
+				print(best)
+		else:  # delta > 0
+			for x in sorted(diff):
+				stack.append(group_1 | {x})
+	return best
+
+
+print(f'Part 1: {dfs(input_nums)[1]}')
+print(f'Part 2: {dfs(input_nums, 4)[1]}')