/*
* File name  : LinkList.cpp
* Function   : 鏈棧的C++實現
* Created on : 2016年4月22日
* Author     : [email protected]
* Copyright  : 歡迎大家和我一起交流學習，轉載請保持原始檔的完整性。
任何單位和個人不經本人允許不得用於商業用途
*/
#include <cstdio>
#include <iostream>

using namespace std;

typedef struct node {
	int data;
	struct node * next;
}Node,*pNode;

typedef struct {
	pNode ptop;
	int count;
}Lstack;

void Lstack_init(Lstack &LS);
void Lstack_push(Lstack &LS, int elem);
bool Lstack_pop(Lstack &LS, int &elem);
bool Lstack_is_empty(Lstack &LS);
int Lstack_get_length(Lstack &LS);
bool Lstack_get_elem(Lstack &LS, int &elem);

int main(int argc, char** argv)
{
	int elem;
	Lstack ls;
	Lstack_init(ls);
	Lstack_pop(ls, elem);
	cout << "Lastack ls is empty ?  " << Lstack_is_empty(ls) << endl;
	Lstack_push(ls, 10);
	Lstack_push(ls, 11);
	Lstack_push(ls, 12);
	cout << "Lastack ls is empty ?  " << Lstack_is_empty(ls) << endl;
	cout << "The length of Lstack ls is " << Lstack_get_length(ls) << endl;
	Lstack_push(ls, 18);
	cout << "The length of Lstack ls is " << Lstack_get_length(ls) << endl;
	Lstack_pop(ls, elem);
	cout << "The pop elem is  " << elem << endl;
	cout << "The length of Lstack ls is " << Lstack_get_length(ls) << endl;
	Lstack_get_elem(ls, elem);
	cout << "The top of Lstack ls is " <<elem << endl;
	Lstack_push(ls, 13);
	cout << "The top of Lstack ls is " << elem << endl;
	Lstack_pop(ls, elem);
	cout << "The top of Lstack ls is " << elem << endl;
	Lstack_pop(ls, elem);
	cout << "The top of Lstack ls is " << elem << endl;
	Lstack_pop(ls, elem);
	cout << "The top of Lstack ls is " << elem << endl;
	Lstack_pop(ls, elem);
	cout << "The top of Lstack ls is " << elem << endl;
	Lstack_pop(ls, elem);
	cout << "The top of Lstack ls is " << elem << endl;


	return 0;
}


void Lstack_init(Lstack &LS)
{
	LS.count = 0;
	LS.ptop = nullptr;
}

void Lstack_push(Lstack &LS, int elem) {
	pNode p = LS.ptop;
	pNode ptmp = nullptr;

	ptmp = new Node;
	ptmp->data = elem;

	ptmp->next = p;
	LS.ptop= ptmp;
	LS.count++;
}

bool Lstack_pop(Lstack &LS, int &elem) {
	pNode p = LS.ptop;
	pNode ptmp = nullptr;
	if (LS.count == 0) {
		cout << "Lstack is empty,can not pop." << endl;
		elem = -1;
		return false;
	}
	ptmp = LS.ptop;
	elem = LS.ptop->data;

	LS.ptop=ptmp->next;
	delete ptmp;
	LS.count--;

	return true;
}

bool Lstack_is_empty(Lstack &LS) {
	return (LS.count == 0) ? true : false;
}

int Lstack_get_length(Lstack &LS) {
	return LS.count;
}

bool Lstack_get_elem(Lstack &LS , int &elem) {
	if (Lstack_is_empty(LS)) {
		cout << "Lstack is empty." << endl;
		return false;
	}
	elem = LS.ptop->data;
	return true;
}