题解 | 合并两个排序的链表

/**
 * struct ListNode {
 *	int val;
 *	struct ListNode *next;
 *	ListNode(int x) : val(x), next(nullptr) {}
 * };
 */
class Solution {
public:
    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     *
     * 
     * @param pHead1 ListNode类 
     * @param pHead2 ListNode类 
     * @return ListNode类
     *用递归的方法/
    ListNode* Merge(ListNode* pHead1, ListNode* pHead2) {
        // write code here
        if(pHead1 == nullptr || pHead2 == nullptr)
        {
            return (pHead1 != nullptr?pHead1:pHead2);
        }
        else if(pHead1->val <= pHead2->val)
        {
            pHead1->next = Merge(pHead1->next,pHead2); 
            return pHead1;
        }
        else
        {
            pHead2->next = Merge(pHead1,pHead2->next);
            return pHead2;
        }
    }
};