Day 2 finished.

rust/day2/src/main.rs

@@ -1,22 +1,48 @@
-use std::fs::read_to_string;
 use std::collections::HashMap;
+use std::fs::read_to_string;
 mod rps;
 
-fn main()
-{
-    // Checking if the file is found.
-    let mut score : u64 = 0;
-    let mut oponent : Vec<String> = read_to_string("input").unwrap().split_whitespace().map(|s| s.to_string()).collect();
-    let mut player = oponent.clone();
-    oponent.retain(|s| s == "A" || s == "B" || s == "C");
-    player.retain(|s| s == "X" || s == "Y" || s == "Z");
-    assert!(oponent.len() == player.len(), "Oponent and Player don't play as many turns.");
-
-    let converter : HashMap<char, rps::RockPaperScissors> = rps::get_converter();
+fn first_strategy(player: &mut Vec<String>, oponent: &Vec<String>) {
+    let mut score: u64 = 0;
+    let converter: HashMap<char, rps::RockPaperScissors> = rps::get_converter();
     for tools in oponent.iter().zip(player.iter_mut()) {
         let o = tools.0.char_indices().next().unwrap().1;
         let p = tools.1.char_indices().next().unwrap().1;
-        score += converter.get(&p).unwrap().battle(converter.get(&o).unwrap());
+        score += converter
+            .get(&p)
+            .unwrap()
+            .battle(converter.get(&o).unwrap());
     }
-    println!("Final score: {}", score);
+    println!("Final score (first method): {}", score);
+}
+
+fn second_strategy(player: &mut Vec<String>, oponent: &Vec<String>) {
+    let mut score: u64 = 0;
+    let converter: HashMap<char, rps::RockPaperScissors> = rps::get_converter();
+    for tools in oponent.iter().zip(player.iter_mut()) {
+        let o = tools.0.char_indices().next().unwrap().1;
+        let oponent_tool = converter.get(&o).unwrap();
+        let player_tool =
+            rps::get_converter_second(tools.1.char_indices().next().unwrap().1, *oponent_tool)
+                .unwrap();
+        score += player_tool.battle(oponent_tool);
+    }
+    println!("Final score (second method): {}", score);
+}
+fn main() {
+    // Checking if the file is found.
+    let mut oponent: Vec<String> = read_to_string("input")
+        .unwrap()
+        .split_whitespace()
+        .map(|s| s.to_string())
+        .collect();
+    let mut player = oponent.clone();
+    oponent.retain(|s| s == "A" || s == "B" || s == "C");
+    player.retain(|s| s == "X" || s == "Y" || s == "Z");
+    assert!(
+        oponent.len() == player.len(),
+        "Oponent and Player don't play as many turns."
+    );
+    first_strategy(&mut player, &oponent);
+    second_strategy(&mut player, &oponent);
 }

rust/day2/src/rps.rs

@@ -1,19 +1,27 @@
 use std::collections::HashMap;
 
-#[derive(Copy, Clone, PartialEq, Eq, Hash)]
+#[derive(Copy, Clone, PartialEq, Eq, Hash, Debug)]
 pub enum RockPaperScissors {
     Rock = 0,
     Paper = 1,
-    Scissors = 2
+    Scissors = 2,
 }
 
-impl RockPaperScissors{
-    pub fn battle(&self, other: &RockPaperScissors) -> u64
-    {
+impl RockPaperScissors {
+    pub fn battle(&self, other: &RockPaperScissors) -> u64 {
         let weight = get_weight();
         let tab = weight.get(&self).unwrap();
         (*self as u64) + 1 + (tab[*other as usize] as u64)
     }
+
+    pub fn from_usize(value: usize) -> Option<RockPaperScissors> {
+        match value {
+            0 => Some(RockPaperScissors::Rock),
+            1 => Some(RockPaperScissors::Paper),
+            2 => Some(RockPaperScissors::Scissors),
+            _ => None
+        }
+    }
 }
 
 pub fn get_converter() -> HashMap<char, RockPaperScissors> {
@@ -27,10 +35,35 @@ pub fn get_converter() -> HashMap<char, RockPaperScissors> {
     ])
 }
 
+pub fn get_converter_second(ch: char, oponent: RockPaperScissors) -> Option<RockPaperScissors> {
+    let binding = get_weight();
+    let weight = binding.get(&oponent).unwrap();
+    match ch {
+        'X' => {
+            let indice = weight
+                .iter()
+                .enumerate()
+                .max_by(|(_, a), (_, b)| a.cmp(b))
+                .map(|(index, _)| index);
+            RockPaperScissors::from_usize(indice.unwrap())
+        }
+        'Y' => Some(oponent),
+        'Z' => {
+            let indice = weight
+                .iter()
+                .enumerate()
+                .min_by(|(_, a), (_, b)| a.cmp(b))
+                .map(|(index, _)| index);
+            RockPaperScissors::from_usize(indice.unwrap())
+        }
+        _ => None,
+    }
+}
+
 fn get_weight() -> HashMap<RockPaperScissors, [u8; 3]> {
     HashMap::from([
-        (RockPaperScissors::Rock, [3,0,6]),
-        (RockPaperScissors::Paper, [6,3,0]),
-        (RockPaperScissors::Scissors, [0,6,3]),
+        (RockPaperScissors::Rock, [3, 0, 6]),
+        (RockPaperScissors::Paper, [6, 3, 0]),
+        (RockPaperScissors::Scissors, [0, 6, 3]),
     ])
 }