题解 | #合并两个排序的链表#

/*
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) {
            return pHead2;
        }
        if (!pHead2) {
            return pHead1;
        }
        ListNode *head = new ListNode(0);
        ListNode *ret = head;
        while(pHead1 && pHead2) {
            if (pHead1->val < pHead2->val) {
                head->next = new ListNode(pHead1->val);
                pHead1 = pHead1->next;
            } else {
                head->next = new ListNode(pHead2->val);
                pHead2 = pHead2->next;
            }
           head = head ->next;
        }
        if (pHead1) {
            head->next = pHead1;
        }
        if (pHead2) {
            head->next = pHead2;
        }
        return ret->next;
    }
};