class Solution {
public:
    ListNode* Merge(ListNode* pHead1, ListNode* pHead2)
    {
        ListNode* Node = NULL;
        if(pHead1 != NULL && pHead2 != NULL){
            if(pHead1->val < pHead2->val){
                Node = pHead1;
                Node->next = Merge(pHead1->next,pHead2);
            }
            else{
                Node = pHead2;
                Node->next = Merge(pHead1,pHead2->next);
            }
        }
        if(pHead1 != NULL)
            Node = pHead1;
        if(pHead2 != NULL)
            Node = pHead2;
        return Node;
    }
};

测试用例:
{1,3,5},{2,4,6}

对应输出应该为:

{1,2,3,4,5,6}

你的输出为:

{2,4,6}