From b8970205512bba2d77e0ca01f3d327b485094cb8 Mon Sep 17 00:00:00 2001
From: Klaiden <itineris24@naver.com>
Date: Tue, 15 Oct 2024 19:52:27 -0700
Subject: [PATCH] week 3

---
 hj/week3/CopyLinkedListWithRandomPointer.cpp | 40 ++++++++++++++++++++
 1 file changed, 40 insertions(+)
 create mode 100644 hj/week3/CopyLinkedListWithRandomPointer.cpp

diff --git a/hj/week3/CopyLinkedListWithRandomPointer.cpp b/hj/week3/CopyLinkedListWithRandomPointer.cpp
new file mode 100644
index 00000000..3d4b833a
--- /dev/null
+++ b/hj/week3/CopyLinkedListWithRandomPointer.cpp
@@ -0,0 +1,40 @@
+/*
+// Definition for a Node.
+class Node {
+public:
+    int val;
+    Node* next;
+    Node* random;
+
+    Node(int _val) {
+        val = _val;
+        next = NULL;
+        random = NULL;
+    }
+};
+*/
+
+class Solution {
+public:
+    Node* copyRandomList(Node* head) {
+        if (!head) return nullptr;
+
+        unordered_map<Node*, Node*> um;
+
+        Node* crnt = head;
+        while (crnt) {
+            Node* node = new Node(crnt->val);
+            um[crnt] = node;
+            crnt = crnt->next;
+        }
+
+        crnt = head;
+        while (crnt) {
+            um[crnt]->next = um[crnt->next];
+            um[crnt]->random = um[crnt->random];
+            crnt = crnt->next;
+        }
+
+        return um[head];
+    }
+};