diff --git a/src/y2021/d02/mod.rs b/src/y2021/d02/mod.rs
index 1afc82e..6a1edf5 100644
--- a/src/y2021/d02/mod.rs
+++ b/src/y2021/d02/mod.rs
@@ -29,3 +29,34 @@ pub mod part1 {
         assert_eq!(solution(INPUT), 1427868);
     }
 }
+pub mod part2 {
+    #[cfg(test)]
+    use super::*;
+
+    pub fn solution(s: &str) -> i32 {
+        let mut pos = 0;
+        let mut depth = 0;
+        let mut aim = 0;
+        s.lines().for_each(|l| {
+            if let Some(v) = l.strip_prefix("up ") {
+                aim -= v.parse::<i32>().unwrap();
+            } else if let Some(v) = l.strip_prefix("down ") {
+                aim += v.parse::<i32>().unwrap();
+            } else {
+                let x = l.strip_prefix("forward ").unwrap().parse::<i32>().unwrap();
+                pos += x;
+                depth += x * aim;
+            }
+        });
+        pos * depth
+    }
+
+    #[test]
+    fn sample() {
+        assert_eq!(solution(SAMPLE), 900);
+    }
+    #[test]
+    fn actual() {
+        assert_eq!(solution(INPUT), 1568138742);
+    }
+}
diff --git a/src/y2021/mod.rs b/src/y2021/mod.rs
index 55e411a..5a4a47d 100644
--- a/src/y2021/mod.rs
+++ b/src/y2021/mod.rs
@@ -1,2 +1,3 @@
 pub mod d01;
 pub mod d02;
+pub mod d03;