刷题四

两个有序链表的合并

class Solution{
    public:
    Node * myMerge(Node * list1, Node * list2){
        if(list1 == null) return list2;
        if(list2 == null) return list1;
        Node * head = new Node();
        Node * p = list1, * q = list2, * m = head;
        while(p != null && q != null){
            if(p->data < q->data){
                m->next = p;
                p = p->next;
            }
            else{
                m->next = q;
                q = q->next;
            }
            m = m->next;
            m->next = null;
        }
        while(p != null)
            m->next = p;
        while(q != null)
            m->next = q;
        return head;
    }
    
    Node * recursiveMerge(Node * list1, Node * list2){
        Node * temp = null;
        if(!list1) return list2;
        if(!list2) return list1;
        if(list1->data < list2->data){
            temp = list1;
            temp->next = recursiveMerge(list1->next,list2);
        }
        else{
            temp = list2;
            temp->next = recursiveMerge(list1,list2->next);
        }
        return temp;
    }
};