[TASK] Day 2 Part 2

functions/src/day2.ts

@@ -18,14 +18,27 @@ class Day2 {
 
   static part2(input: string[]): number {
 
-    
+    let depth = 0;
-    // TODO implement
+    let aim = 0;
-    return 0;
+    let x = 0;
+    for (const entry of input) {
+
+      if (entry.startsWith("up")) {
+        aim -= this.readUnits(entry);
+      } else if (entry.startsWith("down")) {
+        aim += this.readUnits(entry);
+      } else if (entry.startsWith("forward")) {
+        const movement = this.readUnits(entry);
+        depth += aim * movement;
+        x += movement;
+      }
+    }
+    return x * depth;
   }
 
   private static readUnits(input: string): number {
-    return parseInt(input.substr(input.indexOf(' ') + 1));
+    return parseInt(input.substr(input.indexOf(" ") + 1));
   }
 }
 
-export default Day2;
+export default Day2;