From 21a79d76db17a3f9ca3fd8a4082a50ff0dcdcb63 Mon Sep 17 00:00:00 2001
From: Daniel Lin <ephemient@gmail.com>
Date: Thu, 7 Dec 2023 02:32:10 -0500
Subject: [PATCH] Day 7: Camel Cards

---
 README.md          |  2 +-
 py/aoc2023/day7.py | 62 ++++++++++++++++++++++++++++++++++++++++++++++
 py/pyproject.toml  |  1 +
 3 files changed, 64 insertions(+), 1 deletion(-)
 create mode 100644 py/aoc2023/day7.py

diff --git a/README.md b/README.md
index 26a493f5..060f86b2 100644
--- a/README.md
+++ b/README.md
@@ -11,4 +11,4 @@ Development occurs in language-specific directories:
 |[Day4.hs](hs/src/Day4.hs)|[Day4.kt](kt/aoc2023-lib/src/commonMain/kotlin/com/github/ephemient/aoc2023/Day4.kt)|[day4.py](py/aoc2023/day4.py)|[day4.rs](rs/src/day4.rs)|
 |[Day5.hs](hs/src/Day5.hs)|[Day5.kt](kt/aoc2023-lib/src/commonMain/kotlin/com/github/ephemient/aoc2023/Day5.kt)|[day5.py](py/aoc2023/day5.py)|[day5.rs](rs/src/day5.rs)|
 |[Day6.hs](hs/src/Day6.hs)|[Day6.kt](kt/aoc2023-lib/src/commonMain/kotlin/com/github/ephemient/aoc2023/Day6.kt)|[day6.py](py/aoc2023/day6.py)|[day6.rs](rs/src/day6.rs)|
-|[Day7.hs](hs/src/Day7.hs)|[Day7.kt](kt/aoc2023-lib/src/commonMain/kotlin/com/github/ephemient/aoc2023/Day7.kt)|||
+|[Day7.hs](hs/src/Day7.hs)|[Day7.kt](kt/aoc2023-lib/src/commonMain/kotlin/com/github/ephemient/aoc2023/Day7.kt)|[day7.py](py/aoc2023/day7.py)||
diff --git a/py/aoc2023/day7.py b/py/aoc2023/day7.py
new file mode 100644
index 00000000..600bff0c
--- /dev/null
+++ b/py/aoc2023/day7.py
@@ -0,0 +1,62 @@
+"""
+Day 7: Camel Cards
+"""
+
+from collections import Counter
+
+SAMPLE_INPUT = """
+32T3K 765
+T55J5 684
+KK677 28
+KTJJT 220
+QQQJA 483
+"""
+
+
+def _rank(hand: tuple[int]):
+    counts = Counter(x for x in hand if x >= 0).most_common(2)
+    count0 = counts[0][1] if counts else 0
+    count1 = counts[1][1] if len(counts) > 1 else 0
+    jokers = sum(x < 0 for x in hand)
+    # pylint: disable=too-many-return-statements
+    if count0 + jokers >= 5:
+        return 6
+    if count0 + jokers >= 4:
+        return 5
+    if count0 + count1 + jokers >= 5:
+        return 4
+    if count0 + jokers >= 3:
+        return 3
+    if count0 + count1 + jokers >= 4:
+        return 2
+    if count0 + jokers >= 2:
+        return 1
+    return 0
+
+
+def _solve(cards: str, data: str):
+    hands = [
+        (_rank(hand := tuple(map(cards.find, words[0]))), hand, int(words[1]))
+        for line in data.splitlines()
+        if len(words := line.split(maxsplit=1)) == 2
+    ]
+    return sum((i + 1) * bid for i, (_, _, bid) in enumerate(sorted(hands)))
+
+
+def part1(data):
+    """
+    >>> part1(SAMPLE_INPUT)
+    6440
+    """
+    return _solve("23456789TJQKA", data)
+
+
+def part2(data):
+    """
+    >>> part2(SAMPLE_INPUT)
+    5905
+    """
+    return _solve("23456789TQKA", data)
+
+
+parts = (part1, part2)
diff --git a/py/pyproject.toml b/py/pyproject.toml
index 04b1ef3b..d99ca4de 100644
--- a/py/pyproject.toml
+++ b/py/pyproject.toml
@@ -28,6 +28,7 @@ day3 = "aoc2023.day3:parts"
 day4 = "aoc2023.day4:parts"
 day5 = "aoc2023.day5:parts"
 day6 = "aoc2023.day6:parts"
+day7 = "aoc2023.day7:parts"
 
 [tool.black]
 target_version = ["py312"]