【LeetCode热题100】【链表】随机链表的复制

class Solution {
public:
    Node *copyRandomList(Node *head) {
        unordered_map<Node *, Node *> hash;
        Node *cur = head;
        while (cur) {
            hash[cur] = new Node(cur->val);
            cur = cur->next;
        }
        cur = head;
        while (cur) {
            hash[cur]->next = hash[cur->next];
            hash[cur]->random = hash[cur->random];
            cur = cur->next;
        }
        return hash[head];
    }
};