day2 part 2

day2/README.md

@@ -15,7 +15,8 @@ and `C` for Scissors. The second column--" Suddenly, the Elf is called away to h
 The second column, you reason, must be what you should play in response: X for Rock, Y for Paper, and Z for Scissors.
 Winning every time would be suspicious, so the responses must have been carefully chosen.
 
-The winner of the whole tournament is the player with the highest score. Your **total score** is the sum of your scores for
+The winner of the whole tournament is the player with the highest score. Your **total score** is the sum of your scores
+for
 each round. The score for a single round is the score for the **shape you selected** (1 for Rock, 2 for Paper, and 3 for
 Scissors) plus the score for the **outcome of the round** (0 if you lost, 3 if the round was a draw, and 6 if you won).
 
@@ -39,4 +40,22 @@ This strategy guide predicts and recommends the following:
 - The third round is a draw with both players choosing Scissors, giving you a score of 3 + 3 = **6**.
   In this example, if you were to follow the strategy guide, you would get a total score of **15** (8 + 1 + 6).
 
-**What would your total score be if everything goes exactly according to your strategy guide?**
+**What would your total score be if everything goes exactly according to your strategy guide?**
+
+## Part Two
+
+The Elf finishes helping with the tent and sneaks back over to you. "Anyway, the second column says how the round needs
+to end: `X` means you need to lose, `Y` means you need to end the round in a draw, and `Z` means you need to win. Good luck!"
+
+The total score is still calculated in the same way, but now you need to figure out what shape to choose so the round
+ends as indicated. The example above now goes like this:
+
+- In the first round, your opponent will choose Rock (A), and you need the round to end in a draw (Y), so you also
+  choose Rock. This gives you a score of 1 + 3 = **4**.
+- In the second round, your opponent will choose Paper (B), and you choose Rock so you lose (X) with a score of 1 + 0 =
+  **1**.
+- In the third round, you will defeat your opponent's Scissors with Rock for a score of 1 + 6 = **7**. Now that you're
+  correctly decrypting the ultra top secret strategy guide, you would get a total score of **12**.
+
+Following the Elf's instructions for the second column, **what would your total score be if everything goes exactly
+according to your strategy guide?**

day2/main.py

@@ -1,7 +1,4 @@
-from typing import Generator
-
-
-def total_score(data: Generator[list[str]]):
+def total_score_1(data: list[list[str]]) -> int:
     points = {
         "A": 1,
         "B": 2,
@@ -26,9 +23,33 @@ def total_score(data: Generator[list[str]]):
     return score
 
 
-def read_data() -> Generator[list[str]]:
+def total_score_2(data: list[list[str]]) -> int:
+    points = {
+        "A": 0,
+        "B": 1,
+        "C": 2,
+        "X": 1,
+        "Y": 0,
+        "Z": 2,
+    }
+    score = 0
+    for row in data:
+        a, exp = row
+        if points[exp] == 0:
+            # it's a draw
+            score += 3 + points[a] + 1
+        elif points[exp] == 2:
+            # won
+            score += 6 + (points[a] + 1) % 3 + 1
+        else:
+            # lose
+            score += (points[a] - 1) % 3 + 1
+    return score
+
+
+def read_data() -> list[list[str]]:
     with open("./input.txt", "r") as f:
-        return (row.strip().split(" ") for row in f.readlines())
+        return [row.strip().split(" ") for row in f.readlines()]
 
 
 if __name__ == "__main__":
@@ -37,5 +58,5 @@ if __name__ == "__main__":
         ("B", "X"),
         ("C", "Z"),
     ]
-    data = read_data()
-    print(total_score(data))
+    dataset = read_data()
+    print(total_score_2(dataset))