Add day 13 solutions

4 files changed, 110 insertions, 0 deletions

diff --git a/2015/13/.gitignore b/2015/13/.gitignore
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+puzzle-[12].py
diff --git a/2015/13/Makefile b/2015/13/Makefile
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+++ b/2015/13/Makefile
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+all:
+	sed '/START PART 2/,/END PART 2/d' puzzles.py >puzzle-1.py
+	sed '/START PART 1/,/END PART 1/d' puzzles.py >puzzle-2.py
+	chmod +x puzzle-[12].py
+
+.PHONY: clean
+clean:
+	rm -f puzzle-[12].py
diff --git a/2015/13/input b/2015/13/input
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+++ b/2015/13/input
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+Alice would gain 2 happiness units by sitting next to Bob.
+Alice would gain 26 happiness units by sitting next to Carol.
+Alice would lose 82 happiness units by sitting next to David.
+Alice would lose 75 happiness units by sitting next to Eric.
+Alice would gain 42 happiness units by sitting next to Frank.
+Alice would gain 38 happiness units by sitting next to George.
+Alice would gain 39 happiness units by sitting next to Mallory.
+Bob would gain 40 happiness units by sitting next to Alice.
+Bob would lose 61 happiness units by sitting next to Carol.
+Bob would lose 15 happiness units by sitting next to David.
+Bob would gain 63 happiness units by sitting next to Eric.
+Bob would gain 41 happiness units by sitting next to Frank.
+Bob would gain 30 happiness units by sitting next to George.
+Bob would gain 87 happiness units by sitting next to Mallory.
+Carol would lose 35 happiness units by sitting next to Alice.
+Carol would lose 99 happiness units by sitting next to Bob.
+Carol would lose 51 happiness units by sitting next to David.
+Carol would gain 95 happiness units by sitting next to Eric.
+Carol would gain 90 happiness units by sitting next to Frank.
+Carol would lose 16 happiness units by sitting next to George.
+Carol would gain 94 happiness units by sitting next to Mallory.
+David would gain 36 happiness units by sitting next to Alice.
+David would lose 18 happiness units by sitting next to Bob.
+David would lose 65 happiness units by sitting next to Carol.
+David would lose 18 happiness units by sitting next to Eric.
+David would lose 22 happiness units by sitting next to Frank.
+David would gain 2 happiness units by sitting next to George.
+David would gain 42 happiness units by sitting next to Mallory.
+Eric would lose 65 happiness units by sitting next to Alice.
+Eric would gain 24 happiness units by sitting next to Bob.
+Eric would gain 100 happiness units by sitting next to Carol.
+Eric would gain 51 happiness units by sitting next to David.
+Eric would gain 21 happiness units by sitting next to Frank.
+Eric would gain 55 happiness units by sitting next to George.
+Eric would lose 44 happiness units by sitting next to Mallory.
+Frank would lose 48 happiness units by sitting next to Alice.
+Frank would gain 91 happiness units by sitting next to Bob.
+Frank would gain 8 happiness units by sitting next to Carol.
+Frank would lose 66 happiness units by sitting next to David.
+Frank would gain 97 happiness units by sitting next to Eric.
+Frank would lose 9 happiness units by sitting next to George.
+Frank would lose 92 happiness units by sitting next to Mallory.
+George would lose 44 happiness units by sitting next to Alice.
+George would lose 25 happiness units by sitting next to Bob.
+George would gain 17 happiness units by sitting next to Carol.
+George would gain 92 happiness units by sitting next to David.
+George would lose 92 happiness units by sitting next to Eric.
+George would gain 18 happiness units by sitting next to Frank.
+George would gain 97 happiness units by sitting next to Mallory.
+Mallory would gain 92 happiness units by sitting next to Alice.
+Mallory would lose 96 happiness units by sitting next to Bob.
+Mallory would lose 51 happiness units by sitting next to Carol.
+Mallory would lose 81 happiness units by sitting next to David.
+Mallory would gain 31 happiness units by sitting next to Eric.
+Mallory would lose 73 happiness units by sitting next to Frank.
+Mallory would lose 89 happiness units by sitting next to George.
diff --git a/2015/13/puzzles.py b/2015/13/puzzles.py
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index 0000000..33e49e1
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+++ b/2015/13/puzzles.py
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+#!/usr/bin/env python3
+
+import re
+from collections import defaultdict
+from itertools import permutations
+from typing import DefaultDict
+
+
+def main() -> None:
+	with open("input", "r", encoding="utf-8") as f:
+		entries = list(
+			map(
+				lambda e: [e[0], e[1], int(e[2]) if e[1] == "gain" else -int(e[2]), e[3]],
+				(
+					re.split(
+						r"([^ ]+) would (gain|lose) (\d+) happiness units by sitting next to ([^"
+						r" ]+).\n",
+						line,
+					)[1:-1]
+					for line in f.readlines()
+				),
+			)
+		)
+
+	emap: DefaultDict[str, dict[str, int]] = defaultdict(lambda: {})
+	for entry in entries:
+		emap[entry[0]][entry[3]] = entry[2]
+		# START PART 2
+		emap[entry[0]]["Me"] = 0
+		emap["Me"][entry[0]] = 0
+		# END PART 2
+
+	print(
+		max(
+			sum(
+				emap[pair[0]][pair[1]] + emap[pair[1]][pair[0]]
+				for pair in tuple(zip(perm, perm[1:])) + ((perm[-1], perm[0]),)
+			)
+			for perm in permutations(emap)
+		)
+	)
+
+
+if __name__ == "__main__":
+	main()