合并两个链表（c++）

合并两个链表（c++）

输入的链表按照其元素从小到大的顺序排序，输出的链表也按从小到大的顺序排序，请合并两个链表

template<typename E>
Link<E> * LList<E>::mergeList(LList<E> * l1,LList<E>* l2)
{
	Link<E> *list1=l1->head,*list2=l2->head;
	//Make sure list1 and list2 are not empty
	if(list1->next==NULL && list2->next==NULL) return (Link<E>*)0;
    else if(list1->next==NULL) return list2;
	else if (list2 ->next == NULL) return list1;

	Link<E> *newList,* curr,* p,* q;  //Temporary node
	p=list1->next;
	q=list2->next;  //p,q points to the first node
	newList=new Link<E>();
	curr = newList;	
	//Traverse and compare the elements in list1 and list2 until one is empty
	while(p!=NULL && q!=NULL){
		//Find the smallest element and connect to newList, then iterate over the next element
		if(p->element<=q->element){
			curr->next=p;
			p=p->next;
		}else{
			curr->next=q;
			q=q->next;
		}
		curr =curr->next;
	}
	//Link the remaining elements of the comparison to the newList directly
	curr->next=(q==NULL)?p:q;
	return newList;  //return the newList
}