Day 4 - Part 1

Signed-off-by: Anthony Oteri <anthony.oteri@gmail.com>

day-04/src/main.rs

@@ -0,0 +1,93 @@
+#[derive(Debug, Clone, Default, Eq, PartialEq)]
+struct Card {
+    id: usize,
+    winning_numbers: Vec<u32>,
+    game_numbers: Vec<u32>,
+}
+
+impl Card {
+    fn winner(&self) -> usize {
+        let mut count = 0;
+        for guess in &self.winning_numbers {
+            if self.game_numbers.contains(&guess) {
+                count += 1;
+            }
+        }
+
+        let base: usize = 2;
+        if count == 0 {
+            return 0;
+        }
+        base.pow(count - 1)
+    }
+}
+
+fn parse_input(input: &str) -> Vec<Card> {
+    let mut cards = Vec::new();
+
+    for line in input.lines() {
+        let mut card = Card::default();
+
+        let (id_part, numbers_part) = line.split_once(":").unwrap();
+        card.id = id_part
+            .strip_prefix("Card")
+            .unwrap()
+            .trim()
+            .parse::<usize>()
+            .unwrap();
+
+        let (winning_numbers_part, gamen_numbers_part) = numbers_part.split_once("|").unwrap();
+
+        card.winning_numbers = winning_numbers_part
+            .split_whitespace()
+            .map(|n| n.parse::<u32>().unwrap())
+            .collect();
+
+        card.game_numbers = gamen_numbers_part
+            .split_whitespace()
+            .map(|n| n.parse::<u32>().unwrap())
+            .collect();
+
+        cards.push(card);
+    }
+    cards
+}
+
+fn part_1(input: &str) -> usize {
+    let cards = parse_input(input);
+
+    let total: usize = cards.iter().map(|c| c.winner()).sum();
+    total
+}
+
+fn part_2(_input: &str) -> u32 {
+    0
+}
+
+fn main() {
+    let input = include_str!("../input.txt");
+    println!("Part 1: {}", part_1(&input));
+    println!("Part 2: {}", part_2(&input));
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    #[test]
+    fn test_winner() {
+        let card = Card {
+            id: 1,
+            winning_numbers: vec![41, 48, 83, 86, 17],
+            game_numbers: vec![83, 86, 6, 31, 17, 9, 48, 53],
+        };
+
+        assert_eq!(card.winner(), 8)
+    }
+    #[test]
+    fn test_part_1() {
+        let input = include_str!("../test-input.txt");
+
+        assert_eq!(part_1(input), 13);
+    }
+}