190616

#include <iostream>
using namespace std;


class node {
public:
	int data;
	node* next;
};

class mystack {
public:
	node* head;
	mystack() { head = new node(); head->next = NULL; }
	void push(int i);
	void list();
	void pop();
};

void mystack::push(int i)
{
	node* x = new node();
	x->data = i;

	if (head->next == NULL)
	{
		head->next = x;
		return;
	}

	node* p = head;
	while (p->next != NULL)
		p = p->next;
	x->next = p->next;
	p->next = x;

}

void mystack::list()
{
	if (head->next == NULL)
		cout << "無資料" << endl;
	node* p = head;
	while (p->next != NULL)
	{
		p = p->next;
		cout << p->data << endl;
	}
}
void mystack::pop() {

	if (head->next == NULL) {
		cout << "無資料" << endl;
		return;
	}
	node* current = head;
	node* pre = NULL;

	while (current->next != NULL)
	{
		pre = current;
		current = current->next;
	}

	cout << current->data << endl;
	delete current;
	pre->next = NULL;
}

class myqueue {
public:
	node* head;
	myqueue() { head = new node; head->next = NULL; }
	void enqueue(int i);
	void dequeue();
};

void myqueue::enqueue(int i) {
	node* x = new node();
	x->data = i;

	if (head->next == NULL)
	{
		head->next = x;
		return;
	}

	node* p = head;
	while (p->next != NULL)
		p = p->next;
	x->next = p->next;
	p->next = x;
}

void myqueue::dequeue()
{
	if (head->next == NULL)
	{
		cout << "無資料" << endl;
		return;
	}
	node* current = head;
	node* pre = NULL;

	if (current->next != NULL)
	{
		current = current->next;
		cout << current->next << endl;
		pre = current->next;
		delete current;
		head->next = pre;
	}
}

void  main()
{
	mystack st1;
	st1.push(1);
	st1.push(2);
	st1.push(3);
	st1.list();
	st1.pop();
}