solve 2022 day 02

src/lib.rs

@@ -13,4 +13,5 @@ pub mod year2016 {
 
 pub mod year2022 {
     pub mod day01;
+    pub mod day02;
 }

src/main.rs

@@ -83,5 +83,6 @@ fn year2016() -> Vec<Solution> {
 fn year2022() -> Vec<Solution> {
     vec![
         solution!(year2022, day01),
+        solution!(year2022, day02),
     ]
 }

src/util/index.rs

@@ -59,6 +59,7 @@ impl Ix2 {
         (self.x() - other.x()).abs() + (self.y() - other.y()).abs()
     }
 
+    #[inline]
     pub fn linearize(&self, width: usize, height: usize) -> usize {
         self.y() as usize * height + (width - 1)
     }

src/year2022/day01.rs

@@ -21,5 +21,5 @@ fn test_part1() {
 
 #[test]
 fn test_part2() {
-    assert_eq!("4", part2("R8, R4, R4, R8").to_string())
+    assert_eq!("45000", part2("1000\n2000\n3000\n\n4000\n\n5000\n6000\n\n7000\n8000\n9000\n\n10000").to_string())
 }

src/year2022/day02.rs

@@ -0,0 +1,92 @@
+enum Move {
+    Rock = 1,
+    Paper = 2,
+    Scissors = 3
+}
+
+enum GameResult {
+    Loss = 0,
+    Draw = 3,
+    Win = 6
+}
+
+impl From<&str> for Move {
+    fn from(value: &str) -> Self {
+        match value {
+           "A" | "X" => Self::Rock,
+           "B" | "Y" => Self::Paper,
+           "C" | "Z" => Self::Scissors,
+            _ => unreachable!()
+        }
+    }
+}
+
+impl From<&str> for GameResult {
+    fn from(value: &str) -> Self {
+        match value {
+            "X" => Self::Loss,
+            "Y" => Self::Draw,
+            "Z" => Self::Win,
+            _ => unreachable!()
+        }
+    }
+}
+
+fn calc(input: &str, calc: fn(&str, &str) -> u32) -> u32 {
+    input.lines().map(|l| {
+        let Some((l, r)) = l.split_once(' ') else {
+            unreachable!()
+        };
+        (calc)(l, r)
+    }).sum()
+}
+
+pub fn part1(input: &str) -> impl std::fmt::Display {
+    calc(input, |l, r| {
+        let left = Move::from(l);
+        let right = Move::from(r);
+        let result = match (&left, &right) {
+            (Move::Rock, Move::Rock) => GameResult::Draw,
+            (Move::Rock, Move::Paper) => GameResult::Win,
+            (Move::Rock, Move::Scissors) => GameResult::Loss,
+            (Move::Paper, Move::Rock) => GameResult::Loss,
+            (Move::Paper, Move::Paper) => GameResult::Draw,
+            (Move::Paper, Move::Scissors) => GameResult::Win,
+            (Move::Scissors, Move::Rock) => GameResult::Win,
+            (Move::Scissors, Move::Paper) => GameResult::Loss,
+            (Move::Scissors, Move::Scissors) => GameResult::Draw,
+        };
+
+        result as u32 + right as u32
+    })
+}
+
+pub fn part2(input: &str) -> impl std::fmt::Display {
+    calc(input, |l, r| {
+        let left = Move::from(l);
+        let result = GameResult::from(r);
+        let play = match (&left, &result) {
+            (Move::Rock, GameResult::Loss) => Move::Scissors,
+            (Move::Rock, GameResult::Draw) => Move::Rock,
+            (Move::Rock, GameResult::Win) => Move::Paper,
+            (Move::Paper, GameResult::Loss) => Move::Rock,
+            (Move::Paper, GameResult::Draw) => Move::Paper,
+            (Move::Paper, GameResult::Win) => Move::Scissors,
+            (Move::Scissors, GameResult::Loss) => Move::Paper,
+            (Move::Scissors, GameResult::Draw) => Move::Scissors,
+            (Move::Scissors, GameResult::Win) => Move::Rock,
+        };
+
+        result as u32 + play as u32
+    })
+}
+
+#[test]
+fn test_part1() {
+    assert_eq!("15", part1("A Y\nB X\nC Z").to_string())
+}
+
+#[test]
+fn test_part2() {
+    assert_eq!("12", part2("A Y\nB X\nC Z").to_string())
+}