题解 | #合并两个排序的链表#

/**
 * struct ListNode {
 *	int val;
 *	struct ListNode *next;
 * };
 */

/**
 * 
 * @param pHead1 ListNode类 
 * @param pHead2 ListNode类 
 * @return ListNode类
 */
struct ListNode* Merge(struct ListNode* pHead1, struct ListNode* pHead2 ) {
    struct ListNode* head=NULL;
    struct ListNode* tmp=NULL;
    if(pHead1==NULL)
    {
        return pHead2;
    }
    if(pHead2==NULL)
    {
        return pHead1;
    }
    if(pHead1->val<pHead2->val)
    {
        head = pHead1;
        pHead1=pHead1->next;
    }else
    {
        head=pHead2;
        pHead2=pHead2->next;
    }
    tmp=head;
    
    
    while(tmp)
    {
        if(pHead1==NULL)
        {
            tmp->next=pHead2;
            break;
        }
        if(pHead2==NULL)
        {
            tmp->next=pHead1;
            break;
        }
        if(pHead1->val<pHead2->val)
        {
            tmp->next=pHead1;
            pHead1=pHead1->next;
        }
        else
        {
            tmp->next=pHead2;
            pHead2=pHead2->next;
        }
        tmp = tmp->next;
    }
    return head;

}