【leetcode】Merge Two Sorted Lists

 

Merge two sorted linked lists and return it as a new list. The new list should be made by splicing together the nodes of the first two lists.

 

 

 

/**
 * Definition for singly-linked list.
 * struct ListNode {
 *     int val;
 *     ListNode *next;
 *     ListNode(int x) : val(x), next(NULL) {}
 * };
 */
class Solution {
public:
    ListNode *mergeTwoLists(ListNode *l1, ListNode *l2) {
        if(l1==NULL)return l2;
        if(l2==NULL)return l1;
        
        ListNode *ret=NULL;
        if(l1->val<l2->val)
        {
            ret=l1;
            ret->next=mergeTwoLists(l1->next,l2);
        }else
        {
            ret=l2;
            ret->next=mergeTwoLists(l1,l2->next);
        }
        
        return ret;
        
    }
};