Add day2 in OCaml

1 files changed, 115 insertions, 0 deletions

diff --git a/2023/rust/day8/src/lib.rs b/2023/rust/day8/src/lib.rs
new file mode 100644
index 0000000..31f2e2c
--- /dev/null
+++ b/2023/rust/day8/src/lib.rs
@@ -0,0 +1,115 @@
+use std::collections::HashMap;
+
+pub fn part1(input: &str) -> u32 {
+    let mut res: u32 = 0;
+
+    let lines: Vec<String> = input
+        .trim_end()
+        .split('\n')
+        .map(|x| x.to_string())
+        .collect();
+    let ltype = &lines[0];
+    let mut hm: HashMap<String, (String, String)> = HashMap::new();
+    for play in &lines[2..] {
+        hm.insert(
+            play[..3].to_string(),
+            (play[7..10].to_string(), play[12..15].to_string()),
+        );
+    }
+
+    let mut current = "AAA".to_string();
+    for i in ltype.chars().cycle() {
+        current = match i {
+            'R' => hm.get(&current).unwrap().1.clone(),
+            'L' => hm.get(&current).unwrap().0.clone(),
+            _ => panic!("wtf is this?"),
+        };
+        res += 1;
+
+        if current == "ZZZ".to_string() {
+            break;
+        }
+    }
+
+    res
+}
+
+pub fn part2(input: &str) -> u32 {
+    let mut res: u32 = 0;
+
+    let lines: Vec<String> = input
+        .trim_end()
+        .split('\n')
+        .map(|x| x.to_string())
+        .collect();
+    let ltype = &lines[0];
+    let mut hm: HashMap<String, (String, String)> = HashMap::new();
+
+    for play in &lines[2..] {
+        hm.insert(
+            play[..3].to_string(),
+            (play[7..10].to_string(), play[12..15].to_string()),
+        );
+    }
+
+    let mut currents: Vec<String> = hm
+        .keys()
+        .filter(|x| x.ends_with("A"))
+        .into_iter()
+        .map(|x| x.to_string())
+        .collect::<Vec<String>>();
+
+    dbg!("{currents:?}");
+    'o: for i in ltype.chars().cycle() {
+        for k in 0..currents.len() {
+            currents[k] = match i {
+                'R' => hm.get(&currents[k]).unwrap().1.clone(),
+                'L' => hm.get(&currents[k]).unwrap().0.clone(),
+                _ => panic!("wtf is this?"),
+            };
+            res += 1;
+        }
+
+        for current in &currents {
+            if !current.ends_with("Z") {
+                continue 'o;
+            }
+        }
+        break;
+    }
+
+    res
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn example_part1() {
+        let input = include_str!("../example.txt");
+        let result = part1(input);
+        assert_eq!(result, 2);
+    }
+
+    #[test]
+    fn input_part1() {
+        let input = include_str!("../input.txt");
+        let result = part1(input);
+        assert_eq!(result, 21389);
+    }
+
+    #[test]
+    fn example_part2() {
+        let input = include_str!("../example2.txt");
+        let result = part2(input);
+        assert_eq!(result, 12);
+    }
+
+    // #[test]
+    // fn input_part2() {
+    //     let input = include_str!("../input.txt");
+    //     let result = part2(input);
+    //     assert_eq!(result, 248179786);
+    // }
+}