算法与数据结构基础5：C++栈的简单实现

using namespace std;

class Stack
{
public:
// **************************************************************************
// 类的4大函数：构造函数、拷贝构造函数、重载赋值运算符、析构函数
// **************************************************************************
Stack();
Stack(const Stack &Stack);
Stack& operator=(const Stack &Stack);
~Stack();

// **************************************************************************
// 增删改查
// **************************************************************************
void Push(const int& data);
int Pop();

unsigned short Size();
bool IsEmpty();
void PrintStack();

private:
void Free();

private:
typedef struct Node{
Node(int d):data(d),next(NULL){}
int data;
struct Node* next;
}Node;

Node* m_head;
Node* m_tail;
unsigned short m_size;
};

// **************************************************************************
// 私有方法
// **************************************************************************
void Stack::Free()
{
if(m_head){
Node* tmp = NULL;
while(m_head){
tmp = m_head;
m_head = m_head->next;
delete tmp;
}
}
m_head = NULL;
m_tail = NULL;
m_size = 0;
}

// **************************************************************************
// 类的4大函数：构造函数、拷贝构造函数、重载赋值运算符、析构函数
// **************************************************************************
Stack::Stack()
{
m_head = NULL;
m_tail = NULL;
m_size = 0;
}

Stack::Stack(const Stack &Stack)
{
m_head = NULL;
m_tail = NULL;

m_size = Stack.m_size;

if(Stack.m_head){
Node* tmp = Stack.m_head;
Node* q = NULL;
while(tmp){
Node* node = new Node(tmp->data);
if(!m_head){
m_head = node;
q = m_head;
}
else{
q->next = node;
q = node;
}
tmp = tmp->next;
}
m_tail = q;
}
else{
m_head = NULL;
m_tail = NULL;
}
}

Stack& Stack::operator=(const Stack &Stack)
{
Free();

m_size = Stack.m_size;

if(Stack.m_head){
Node* tmp = Stack.m_head;
Node* q = NULL;
while(tmp){
Node* node = new Node(tmp->data);
if(!m_head){
m_head = node;
q = m_head;
}
else{
q->next = node;
q = node;
}

tmp = tmp->next;
}
m_tail = q;
}
else{
m_head = NULL;
m_tail = NULL;
}

return *this;
}

Stack::~Stack()
{
if (m_head){
Node* tmp = m_head;
while (tmp){
m_head = m_head->next;
delete tmp;
tmp = m_head;
}
}
m_head = NULL;
m_tail = NULL;
}

// **************************************************************************
// 增删改查
// **************************************************************************
void Stack::Push(const int& data)
{
Node* tmp = new Node(data);
if (!m_head) {
m_head = tmp;
m_tail = tmp;
}
else{
tmp->next = m_head;
m_head = tmp;
}
++m_size;
}

int Stack::Pop()
{
assert(m_size > 0);

Node* tmp = m_head;
m_head = m_head->next;

int val = tmp->data;
delete tmp;
–m_size;

return val;
}

unsigned short Stack::Size()
{
return m_size;
}

bool Stack::IsEmpty()
{
return (m_size == 0);
}

void Stack::PrintStack()
{
cout << "size : " << m_size << " , content : ";
if (m_head){
Node* tmp = m_head;
while (tmp){
cout << tmp->data << " -> ";
tmp = tmp->next;
}
}

cout << "NULL" << endl;
}

using namespace std;

int main()
{
Stack stack;
for (int i = 1; i < 5; ++i){
stack.Push(i);
}
stack.PrintStack();

Stack stackCopy(stack);
stackCopy.PrintStack();

Stack stackAssig;
stackAssig = stack;
stackAssig.PrintStack();

int pop = stack.Pop();
cout << "pop:" << pop << endl;
stack.PrintStack();

system("pause");

return 0;
}