命令模式-JZTXT

[实验任务一]：多次撤销和重复的命令模式
某系统需要提供一个命令集合（注：可以使用链表，栈等集合对象实现），用于存储一系列命令对象，并通过该命令集合实现多次undo()和redo()操作，可以使用加法运算来模拟实现。
1. 提交类图；

2. 提交源代码；

#include <iostream>
#include <stack>
using namespace std;
int num = 0;
class AbstractCommand
{
public:
    virtual int execute(int value) = 0;
    virtual int undo() = 0;
    virtual int redo() = 0;
};
class Adder
{

public:
    int add(int value)
    {
        num += value;
        return num;
    }
};
class AddCommand : public AbstractCommand
{
private:
    Adder *adder;
    stack<int> unStack;
    stack<int> reStack;

public:
    int undo()
    {
        // adder= new Adder();
        int i = 0;
        if (unStack.empty())
        {
            i = -1;
        }
        else
        {
            int pop = unStack.top();
            reStack.push(pop);
            unStack.pop();
            if (!unStack.empty())
            { // 判断弹出数据后是否为空，如果为空，说明已撤回到最原始状态
                i = unStack.top();
            }
        }

        return i;
    }
    int redo()
    {
        // adder= new Adder();
        int i = 0;
        if (reStack.empty())
        {
            i = -1;
        }
        else
        { 
            int pop = reStack.top();
            reStack.pop();
            unStack.push(pop);
            i = pop;
        }
        return i;
    }
    int execute(int value)
    {

        int v = 0;
        if (unStack.empty())
        { // 说明还没有数据
            v = adder->add(value);
            unStack.push(v);
        }
        else
        { // 需要更新两个栈中的内容，并计算结果,其中返回栈应该更新，重复栈应该清空
            v = adder->add(value);
            unStack.push(v);
            if (!reStack.empty())
            {
                for (int i = 0; i < reStack.size(); i++)
                {
                    // reStack.top();
                    // reStack.pop();
                }
            }
        }
        return v;
    }
};
class CalculatorForm
{
private:
    AbstractCommand *command;

public:
    void setCommand(AbstractCommand *command)
    {
        this->command = command;
    }
    void compute(int value)
    {
        command->execute(value);
    }
    void undo()
    {
        int i = command->undo();
        if (i == -1)
        {
            cout << "缓存中已不存在数据" << endl;
        }
        else
        {
            cout << "执行成功，运算结果是：" << i << endl;
        }
    }
    void redo()
    {
        int i = command->redo();
        if (i == -1)
        {
            cout << "已恢复至最新数据" << endl;
        }
        else
        {
            cout << "执行成功，运算结果是：" << i << endl;
        }
    }
};
int main()
{
    CalculatorForm *form = new CalculatorForm();
    AddCommand *command = new AddCommand();
    form->setCommand(command);
    // 计算
    cout << "------计算过程------" << endl;
    form->compute(1);
    form->compute(2);
    form->compute(3);
    form->compute(4);
    // 多次撤回
    cout << "------撤回过程------" << endl;
    form->undo();
    form->undo();
    form->undo();
    form->undo();
    form->undo();
    // 多次恢复
    cout << "------恢复过程------" << endl;
    form->redo();
    form->redo();
    form->redo();
    form->redo();
    form->redo();
    return 0;
}