第三十四课 栈的概念及实现（上）

 

 

这种使用原生数组作为存储容器的栈也简称顺序栈。

添加Stack.h文件：

#ifndef STACK_H
#define STACK_H

#include "Object.h"

namespace DTLib
{

template < typename T >
class Stack : public Object
{
public:
    virtual void push(const T& e) = 0;
    virtual void pop() = 0;
    virtual T top() const = 0;
    virtual void clear() = 0;
    virtual int size() const = 0;
};

}

#endif // STACK_H

添加StaticStack.h文件：

#ifndef STATICSTACK_H
#define STATICSTACK_H

#include "Stack.h"
#include "Exception.h"

namespace DTLib
{

template < typename T, int N >
class StaticStack : public Stack<T>
{
protected:
    T m_space[N];
    int m_top;
    int m_size;
public:
    StaticStack()
    {
        m_top = -1;
        m_size = 0;
    }

    int capacity() const
    {
        return N;
    }

    void push(const T& e)
    {
        if( m_size < N )
        {
            m_space[m_top + 1] = e;  //先赋值，保证异常安全
            m_top++;
            m_size++;
        }
        else
        {
            THROW_EXCEPTION(InvalidOperationException, "No space in current stack ...");
        }
    }

    void pop()
    {
        if( m_size > 0 )
        {
            m_top--;
            m_size--;
        }
        else
        {
            THROW_EXCEPTION(InvalidOperationException, "No element in current stack ...");
        }
    }

    T top() const
    {
        if( m_size > 0 )
        {
            return m_space[m_top];
        }
        else
        {
            THROW_EXCEPTION(InvalidOperationException, "No element in current stack ...");
        }
    }

    void clear()
    {
        m_top = -1;
        m_size = 0;
    }

    int size() const
    {
        return m_size;
    }
};

}

#endif // STATICSTACK_H

测试程序如下：

#include <iostream>
#include "StaticStack.h"

using namespace std;
using namespace DTLib;


int main()
{
    StaticStack<int, 5> stack;

    for(int i = 0; i < 5; i++)
    {
        stack.push(i);
    }

    while( stack.size() > 0 )
    {
        cout << stack.top() << endl;
        stack.pop();
    }

    return 0;
}

运行结果如下：

小结：