Day 8 Part 1 complete

src/solutions/day08.rs

@@ -1,3 +1,5 @@
+use std::collections::HashMap;
+
 use super::Solution;
 
 pub struct Day08 {}
@@ -5,9 +7,37 @@ pub struct Day08 {}
 impl Solution for Day08 {
     fn part1(
         &self,
-        _input: &mut Vec<String>,
+        input: &mut Vec<String>,
     ) -> Result<Box<dyn std::fmt::Display + Sync>, Box<dyn std::error::Error>> {
-        Ok(Box::new("Ready"))
+        let instructions: String = input[0].clone();
+        let mut map: HashMap<String, (String, String)> = HashMap::new();
+
+        self.populate_map(&input[2..input.len()], &mut map)?;
+
+        let mut count = 0u32;
+        let mut current = map.get("AAA").unwrap();
+        let mut found = false;
+
+        while !found {
+            for i in instructions.chars() {
+                count += 1;
+                let next: &String;
+                match i {
+                    'L' => next = &current.0,
+                    'R' => next = &current.1,
+                    _ => {
+                        continue;
+                    }
+                }
+                if next == "ZZZ" {
+                    found = true;
+                    break;
+                }
+                current = map.get(next).unwrap();
+            }
+        }
+
+        Ok(Box::new(count))
     }
 
     fn part2(
@@ -22,7 +52,33 @@ impl Solution for Day08 {
     }
 }
 
-impl Day08 {}
+impl Day08 {
+    fn populate_map<'a>(
+        &self,
+        input: &[String],
+        map: &mut HashMap<String, (String, String)>,
+    ) -> Result<(), Box<dyn std::error::Error>> {
+        for p in input {
+            let mut x = p.split('=');
+
+            let key = x.nth(0).unwrap().trim().to_owned();
+            let (l, r) = x.nth(0).unwrap().split_at(6);
+            map.insert(
+                key,
+                (
+                    l.to_owned()
+                        .replace(",", "")
+                        .replace("(", "")
+                        .trim()
+                        .to_owned(),
+                    r.trim().to_owned().replace(")", ""),
+                ),
+            );
+        }
+
+        Ok(())
+    }
+}
 
 /// Test from puzzle input
 #[cfg(test)]
@@ -44,7 +100,7 @@ mod test {
             .unwrap()
             .to_string();
 
-        assert_eq!(answer, "Ready");
+        assert_eq!(answer, "6");
     }
 
     #[test]