#include<iostream>
#include<stdio.h>
#include<math.h>
#define LEN sizeof(struct Nodelist)
using namespace std;
typedef struct Nodelist
{
	int data;;
	struct Nodelist *next;
}Nodelist;
//函式宣告
void Error(char *s);                      //錯誤處理函式
Nodelist *CreatNode(void);                 //後插法建立單鏈表
Nodelist *ReverseList(Nodelist *head);     //就地逆置函式
void MeryNode(Nodelist &l1, Nodelist &l2); //就地歸併函式
void printNode(Nodelist L);                //輸出函式
//函式定義
void Error(char *s)   //錯誤處理函式
{
	cout << s << endl;
	exit(1);
}
Nodelist *CreatNode(void)  //後插法建立單鏈表
{
	int  i, n;
	Nodelist *head, *p, *q;
	p = q = NULL;
	head = NULL;
	cout << "請輸入您要建立的連結串列長度:";
	cin >> n;
	cout << "請輸入您要輸入的資料:" << endl;;
	for (i = 0; i<n; ++i)
	{

		p = (Nodelist *)malloc(LEN);
		cin >> p->data;
		if (head == NULL)  //單個結點
			q = head = p;
		else
			q->next = p;
		q = p;
	}
	p->next = NULL;
	return head;
}
void printNode(Nodelist L)  //將連結串列依次資料輸出
{
	Nodelist *p = &L;
	while (p)
	{
		cout << p->data << " ";
		p = p->next;
	}
	cout << endl;
}
Nodelist *ReverseList(Nodelist *head)  //就地逆置函式
{ 
	Nodelist *p, *q, *r;
	p = head;
	q = r = NULL;
	while (p)
	{
		q = p->next;
		p->next = r;
		r = p;
		p = q;
	}
	return r;
}
void MeryNode(Nodelist &l1, Nodelist &l2) //就地歸併函式
{
	Nodelist *pa, *pb, *pc, *pd;
	pa = &l1;
	pb = &l2;
	pc = pa;
	while (pa&&pb)
	{
		if (pa->data <= pb->data)
		{
			pc = pa;
			pa = pa->next;
		}
		else
		{
			pd = pb->next;
			pb->next = pa;
			pc->next = pb;
			pc = pb;
			pb = pd;
		}
	}
	if (pb!=NULL)
		pc->next = pb;
}
int main()   //主函式測試
{
	Nodelist *head1, *head2;

	head1 = CreatNode();
	cout << "逆置前的連結串列資料：" << endl;
	printNode(*head1);
	Nodelist *head3 = ReverseList(head1);
	cout << "逆置後的連結串列資料：" << endl;
	printNode(*head3);

	head2 = CreatNode();
	cout << "逆置前的連結串列資料：" << endl;
	printNode(*head2);
	Nodelist *head4 = ReverseList(head2);
	cout << "逆置後的連結串列資料：" << endl;
	printNode(*head4);

	cout << "就地歸併後：" << endl;
	MeryNode(*head3, *head4);
	printNode(*head3);

	return 0;
}