Improve hand creation

src/day02/mod.rs

@@ -5,6 +5,12 @@ struct Hand {
     pub letter: char
 }
 
+impl From<&str> for Hand {
+    fn from(s: &str) -> Self {
+        Self { letter: s.0.chars().next().unwrap() }
+    }
+}
+
 impl Hand {
     pub fn score(&self) -> i32 {
         match self.letter {
@@ -77,12 +83,14 @@ pub fn run() {
         .lines()
         .map(|l| {
             let hands = l
-                .split(' ')
-                .map(|s|Hand { letter: s.chars().next().unwrap() })
-                .collect::<Vec<_>>();
+                .split_once(' ')
+                .map(|c|
+                    (c.0.into(),
+                     c.1.into())
+                ).unwrap();
             Round {
-                enemy: hands[0].clone(),
-                me: hands[1].clone(),
+                enemy: hands.0,
+                me: hands.1,
             }
         }).map(|r|(r.score(), r.score_b()))
         .fold((0, 0), |agg, cur|(agg.0 + cur.0, agg.1 + cur.1));