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.
合并两个有序链表
/** * 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) { ListNode *head=new ListNode(0); ListNode *t=head; while(l1!=NULL && l2!=NULL) { if(l1->val<l2->val) { t->next=l1; l1=l1->next; }else{ t->next=l2; l2=l2->next; } t =t->next; } if(l1!=NULL) t->next=l1; if(l2!=NULL) t->next=l2; return head->next; } };