LeetCode-M-Copy List with Random Pointe

題意

A linked list is given such that each node contains an additional random pointer which could point to any node in the list or null.

Return a deep copy of the list.

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解法

回頭補上

實現

/**
 * Definition for singly-linked list with a random pointer.
 * struct RandomListNode {
 *     int label;
 *     RandomListNode *next, *random;
 *     RandomListNode(int x) : label(x), next(NULL), random(NULL) {}
 * };
 */
class Solution {
public:
    RandomListNode *splitCopyList(RandomListNode* head){
        RandomListNode* copyhead = head->next;
        RandomListNode* cur = head;
        while(cur != NULL){
            RandomListNode* ccur = cur->next;
            cur->next = ccur->next;
            if(cur->next != NULL) ccur->next = cur->next->next;
            else ccur->next = NULL;
            cur = cur->next;
        }
        return copyhead;
    }

    RandomListNode *copyRandomRela(RandomListNode* head){
        RandomListNode* cur = head;
        while(cur != NULL){
            RandomListNode* random = cur->random;
            RandomListNode* ccur = cur->next;
            if(random != NULL){
                ccur->random = random->next;
            }
            cur = ccur->next;
        }
        return head;
    }
    RandomListNode *copyNextRela(RandomListNode* head){
        RandomListNode* cur = head;
        while(cur != NULL){
            RandomListNode* ccur = new RandomListNode(cur->label);
            ccur->next = cur->next;
            cur->next = ccur;
            cur = ccur->next;
        }
        return head;
    }
    RandomListNode *copyRandomList(RandomListNode *head) {
        if(head == NULL) return head;
        RandomListNode* nextHead = copyNextRela(head);
        RandomListNode* randomHead = copyRandomRela(head);
        RandomListNode* copyHead = splitCopyList(randomHead);
        return copyHead;
    }
};