Day two part 1

two.rs

@@ -0,0 +1,50 @@
+const SCORE_WIN: u32 = 6;
+const SCORE_DRAW: u32 = 3;
+
+const SCORE_ROCK: u32 = 1;
+const SCORE_PAPER: u32 = 2;
+const SCORE_SCISSORS: u32 = 3;
+
+fn main() {
+    let buf = std::fs::read_to_string("two.txt").unwrap();
+    let mut total = 0u32;
+
+    for s in buf.split("\n") {
+        if s.is_empty() {
+            continue;
+        }
+        let chars = s.chars().collect::<Vec<_>>();
+        let opponent = chars[0];
+        let choice = chars[2];
+
+        total += match choice {
+            'X' => SCORE_ROCK,
+            'Y' => SCORE_PAPER,
+            'Z' => SCORE_SCISSORS,
+            _ => 0,
+        };
+
+        if draw(choice, opponent) {
+            total += SCORE_DRAW;
+            continue;
+        }
+
+        if won(choice, opponent) {
+            total += SCORE_WIN;
+        }
+    }
+
+    println!("{}", total);
+}
+
+fn won(choice: char, opponent: char) -> bool {
+    return choice == 'X' && opponent == 'C'
+        || choice == 'Y' && opponent == 'A'
+        || choice == 'Z' && opponent == 'B';
+}
+
+fn draw(choice: char, opponent: char) -> bool {
+    return choice == 'X' && opponent == 'A'
+        || choice == 'Y' && opponent == 'B'
+        || choice == 'Z' && opponent == 'C';
+}