题解 | 合并两个排序的链表

/**
 * struct ListNode {
 *	int val;
 *	struct ListNode *next;
 * };
 */
/**
 * 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
 */
struct ListNode* Merge(struct ListNode* pHead1, struct ListNode* pHead2 ) {
    // write code here
    if(!(pHead1||pHead2))
    {
        return NULL;
    }
    if(!(pHead1&&pHead2))
    {
        if(pHead1)
        {
            return pHead1;
        }
        else {
        return pHead2;
        }
    }
    struct ListNode* p,*p1;
    p = pHead1->val<=pHead2->val?pHead1:pHead2;
    while(pHead1&&pHead2)
    {
        if(pHead1->val<=pHead2->val)
        {
            if(p1!=NULL)
            {
                p1->next =pHead1;
            }
            p1 = pHead1;
            pHead1 = pHead1->next;
        }
        else 
        {
            if(p1!=NULL)
            {
                p1->next = pHead2;
            }
        p1 = pHead2;
        pHead2 = pHead2->next;
        }
       
    }
     p1->next = pHead1?pHead1:pHead2;
        return p;

        
}