From ca10b3ac7876d81fdf4ae2c17c1b885ac0726d34 Mon Sep 17 00:00:00 2001
From: HangCcz <hangchen1128@gmail.com>
Date: Sat, 16 Apr 2022 20:33:09 -0400
Subject: [PATCH] 138-Copy-List-with-Random-Pointer.js

---
 .../138-Copy-List-with-Random-Pointer.js      | 22 +++++++++++++++++++
 1 file changed, 22 insertions(+)
 create mode 100644 javascript/138-Copy-List-with-Random-Pointer.js

diff --git a/javascript/138-Copy-List-with-Random-Pointer.js b/javascript/138-Copy-List-with-Random-Pointer.js
new file mode 100644
index 000000000..668b38f42
--- /dev/null
+++ b/javascript/138-Copy-List-with-Random-Pointer.js
@@ -0,0 +1,22 @@
+/**
+ * @param {Node} head
+ * @return {Node}
+ */
+var copyRandomList = function (head) {
+  let map = new Map();
+  let ptr = head;
+
+  while (ptr) {
+    // map old - new
+    map.set(ptr, new Node(ptr.val, null, null));
+    ptr = ptr.next;
+  }
+
+  ptr = head;
+  while (ptr) {
+    map.get(ptr).next = map.get(ptr.next) || null;
+    map.get(ptr).random = map.get(ptr.random) || null;
+    ptr = ptr.next;
+  }
+  return map.get(head);
+};