[剑指offer] 25. 复杂链表的复制

class Solution
{
public:
  RandomListNode *Clone(RandomListNode *pHead)
  {
    if (pHead == NULL)
      return NULL;
    RandomListNode *newHead = new RandomListNode(pHead->label);
    RandomListNode *curNode1 = pHead;
    RandomListNode *curNode2 = newHead;
    // 新旧链表形成Z链
    while (curNode1)
    {
      curNode2->next = curNode1->next;
      curNode1->next = curNode2;

      curNode1 = curNode2->next;
      curNode2 = curNode1 == NULL ? NULL : new RandomListNode(curNode1->label);
    }

    curNode1 = pHead;
    curNode2 = newHead;
    // 新链添加random
    while (curNode1)
    {
      curNode2->random = curNode1->random == NULL ? NULL : curNode1->random->next;
      curNode1 = curNode2->next;
      curNode2 = curNode1 == NULL ? NULL : curNode1->next;
    }

    curNode1 = pHead;
    curNode2 = newHead;
    // 脱链
    while (curNode1)
    {
      curNode1->next = curNode2->next;
      curNode2->next = curNode1->next == NULL ? NULL : curNode1->next->next;

      curNode1 = curNode1->next;
      curNode2 = curNode2->next;
    }
    return newHead;
  }
};

class Solution
{
public:
  RandomListNode *Clone(RandomListNode *pHead)
  {
    if (pHead == NULL)
      return NULL;

    map<RandomListNode *, RandomListNode *> m;
    RandomListNode *curNode1 = pHead;
    RandomListNode *curNode2 = new RandomListNode(curNode1->label);
    RandomListNode *newHead = curNode2;
    m[curNode1] = curNode2;
    while (curNode1)
    {
      curNode2->next = curNode1->next == NULL ? NULL : new RandomListNode(curNode1->next->label);
      curNode1 = curNode1->next;
      curNode2 = curNode2->next;
      m[curNode1] = curNode2;
    }

    curNode1 = pHead;
    curNode2 = newHead;
    while (curNode1)
    {
      curNode2->random = m[curNode1->random];
      curNode1 = curNode1->next;
      curNode2 = curNode2->next;
    }
    return newHead;
  }
};