diff --git a/.vscode/launch.json b/.vscode/launch.json
index 0804bd6..3aa9c12 100644
--- a/.vscode/launch.json
+++ b/.vscode/launch.json
@@ -7,6 +7,7 @@
             "args": [
                 "--experimental-specifier-resolution=node",
                 "--trace-warnings",
+                "--stack-size=65500",
                 // "--loader",
                 // "ts-node/esm",
                 "--import",
diff --git a/16.2.ts b/16.2.ts
index 1440b81..64e6707 100644
--- a/16.2.ts
+++ b/16.2.ts
@@ -1,19 +1,16 @@
 import { open } from 'node:fs/promises';
 
 const path = './inputs/16'
+
 const file1 = (await open(path))
-const file2 = (await open(path))
-
 const input = (await file1.readFile()).toString().split('\n').map(e => e.split(""))
-const process = (await file2.readFile()).toString().split('\n').map(e => e.split("").map(e => [] as Coords[]))
-
 type Coords = { x: number, y: number }
 
-function moveForward({ x, y }: Coords, direction: Coords) {
-    ray({ x: x + direction.x, y: y + direction.y }, direction)
+function moveForward({ x, y }: Coords, direction: Coords, process: Coords[][][]) {
+    ray({ x: x + direction.x, y: y + direction.y }, direction, process)
 }
 
-function ray({ x, y }: Coords, direction: Coords) {
+function ray({ x, y }: Coords, direction: Coords, process: Coords[][][]) {
 
     if (input[y] === undefined) {
         return
@@ -27,48 +24,72 @@ function ray({ x, y }: Coords, direction: Coords) {
     if (process[y][x].find(e => e.x == direction.x && e.y == direction.y)) {
         return
     }
-    process[y][x].push(direction)
+    process[y][x].push({ ...direction })
 
 
 
     if (current === '\\') {
         direction = { x: direction.y, y: direction.x }
-        moveForward({ x, y }, direction)
+        moveForward({ x, y }, direction, process)
         return
     }
 
     if (current === '/') {
         direction = { x: -direction.y, y: -direction.x }
-        moveForward({ x, y }, direction)
+        moveForward({ x, y }, direction, process)
         return
     }
 
     if (current === '|') {
         if (direction.x === 0) {
-            moveForward({ x, y }, direction)
+            moveForward({ x, y }, direction, process)
             return
         }
-        moveForward({ x, y }, { x: 0, y: 1 })
-        moveForward({ x, y }, { x: 0, y: -1 })
+        moveForward({ x, y }, { x: 0, y: 1 }, process)
+        moveForward({ x, y }, { x: 0, y: -1 }, process)
         return
     }
 
     if (current === '-') {
         if (direction.y === 0) {
-            moveForward({ x, y }, direction)
+            moveForward({ x, y }, direction, process)
             return
         }
-        moveForward({ x, y }, { x: 1, y: 0 })
-        moveForward({ x, y }, { x: -1, y: 0 })
+        moveForward({ x, y }, { x: 1, y: 0 }, process)
+        moveForward({ x, y }, { x: -1, y: 0 }, process)
         return
     }
-    moveForward({ x, y }, direction)
+    moveForward({ x, y }, direction, process)
 }
 
-ray({ x: 0, y: 0 }, { x: 1, y: 0 })
+async function computeAt({ x, y }: Coords, direction: Coords) {
 
-console.log(process.flat(1).reduce((acc, e) => e.length > 0 ? acc + 1 : acc, 0))
+    const file2 = (await open(path))
+
+    const process = (await file2.readFile()).toString().split('\n').map(e => e.split("").map(e => [] as Coords[]))
+    const close = Promise.all([file1.close(), file2.close()])
+
+    ray({ x, y }, direction, process)
+
+    await close
+
+    return process.flat(1).reduce((acc, e) => e.length > 0 ? acc + 1 : acc, 0)
 
 
+}
 
-await Promise.all([file1.close(), file2.close()])
+const promises: Promise<number>[] = []
+const height = input.length
+const width = input[0].length
+for (let i = 0; i < height; i++) {
+    promises.push(computeAt({ x: 0, y: i }, { x: 1, y: 0 }))
+    promises.push(computeAt({ x: width - 1, y: i }, { x: -1, y: 0 }))
+}
+
+for (let i = 0; i < width; i++) {
+    promises.push(computeAt({ x: i, y: 0 }, { x: 0, y: 1 }))
+    promises.push(computeAt({ x: i, y: height - 1 }, { x: 0, y: -1 }))
+}
+
+const numbers = await Promise.all(promises)
+console.log(Math.max(...numbers))