面试题26 复杂链表的复制

题目描述

输入一个复杂链表（每个节点中有节点值，以及两个指针，一个指向下一个节点，另一个特殊指针指向任意一个节点）。

/*
struct RandomListNode {
    int label;
    struct RandomListNode *next, *random;
    RandomListNode(int x) :
            label(x), next(NULL), random(NULL) {
    }
};
*/
class Solution {
public:
    void CloneNodes(RandomListNode *pHead){
        RandomListNode *pNode = pHead;
        while (pNode != NULL){
            RandomListNode *pClone = new RandomListNode(pNode->label);
            pClone->next = pNode->next;
            pClone->random = NULL;
            pNode->next = pClone;
            pNode = pClone->next;
        }
    }
    
    void ConnectRandomNodes(RandomListNode *pHead){
        RandomListNode *pNode = pHead;
        while (pNode != NULL){
            RandomListNode *pClone = pNode->next;
            if (pNode->random != NULL){
                pClone->random = pNode->random->next;
            }
            pNode = pClone->next;
        }
    }
    
    RandomListNode* ReconnectNodes(RandomListNode *pHead){
        RandomListNode *pNode = pHead;
        RandomListNode *pCloneHead = NULL;
        RandomListNode *pCloneNode = NULL;
        
        if (pNode != NULL){
            pCloneHead = pCloneNode = pNode->next;
            pNode->next = pCloneHead->next;
            pNode = pNode->next;
        }
        
        while (pNode != NULL){
            pCloneNode->next = pNode->next;
            pCloneNode = pCloneNode->next;
            pNode->next = pCloneNode->next;
            pNode = pNode->next;
        }
        return pCloneHead;
    }
    
    
    RandomListNode* Clone(RandomListNode* pHead)
    {
        CloneNodes(pHead);
        ConnectRandomNodes(pHead);
        return ReconnectNodes(pHead);
    }
};