C++题解 | #链表中倒数最后k个结点#

大致分析后，不难发现此处为一个递归过程。

/*
struct ListNode {
    int val;
    struct ListNode *next;
    ListNode(int x) :
            val(x), next(NULL) {
    }
};*/
class Solution {
public:
 ListNode* Merge(ListNode* pHead1, ListNode* pHead2)
 {
     if (pHead1 == NULL) 
         return pHead2;
     if (pHead2 == NULL) 
         return pHead1;
     if (pHead1->val <= pHead2->val) {
         pHead1->next = Merge(pHead1->next, pHead2);
         return pHead1;
     }
     else {
         pHead2->next = Merge(pHead1, pHead2->next);
         return pHead2;
     }
 }
};