实验5 类的继承、派生和多态(2)

实验目的

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1. 理解运行时多态

2. 掌握虚函数和抽象类

实验准备

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1. 概念
多态，运行时多态

虚函数， 纯虚函数， 抽象类

2. 语法和应用

虚函数的定义和使用
纯虚函数、抽象类的定义和使用

实验结论

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Part3：简单编程练习//还没试过加入音频文件

#ifndef MACHINEPETS_H
#define MACHINEPETS_H
#include<string>
using namespace std;
class MachinePets{
public:
    MachinePets(const string s="nameless");
    virtual string talk()=0;
    string getNickname();
private:
    string nickname;
};
#endif

#include"machinepets.h"


MachinePets::MachinePets(string s/*="nameless"*/):nickname(s){}



string MachinePets::getNickname(){
        return nickname;
    }

#ifndef PETCATS_H
#define PETCATS_H
#include"machinepets.h"
#include<string>
using namespace std;
class PetCats:public MachinePets{
public:
    PetCats(const string s);
    string talk();
};
#endif

#include"petcats.h"
#include"machinepets.h"



PetCats::PetCats(const string s):MachinePets(s){
}



string PetCats::talk(){
    return "meow~";
}

#ifndef PETDOGS_H
#define PETDOGS_H
#include"machinepets.h"
#include<string>
using namespace std;
class PetDogs:public MachinePets{
public:
    PetDogs(const string s);
    string talk();
};
#endif

#include"petdogs.h"
#include"machinepets.h"



PetDogs::PetDogs(const string s):MachinePets(s){}



string PetDogs::talk(){
    return "woof~";
}

// 主函数
#include"machinepets.h"
#include"petdogs.h"
#include"petcats.h"
#include<iostream>
#include<string>
#include<cstdlib>
using namespace std;


void play(MachinePets * pet){
    cout<<pet->getNickname()<<' '<<"says"<<' '<<pet->talk()<<endl;
}



int main() {
PetCats cat("miku");
PetDogs dog("da huang");
play(&cat); // 按照play()形参，传递参数
play(&dog); // 按照play()形参，传递参数
system("pause");
return 0;
}

 Part4：应用编程实践: 简单RPG游戏补足与丰富//只是补足了，以后继续完善

//=======================
//        container.h
//=======================

// The so-called inventory of a player in RPG games
// contains two items, heal and magic water

#ifndef _CONTAINER        // Conditional compilation
#define _CONTAINER

class container        // Inventory
{
protected:
    int numOfHeal;            // number of heal
    int numOfMW;            // number of magic water
public:
    container();            // constuctor
    void set(int heal_n, int mw_n);    // set the items numbers
    int nOfHeal();            // get the number of heal
    int nOfMW();            // get the number of magic water
    void display();            // display the items;
    bool useHeal();            // use heal
    bool useMW();            // use magic water
};

#endif

//=======================
//        container.cpp
//=======================

// default constructor initialise the inventory as empty
#include"container.h"
#include<iostream>
using namespace std;
container::container()
{
    set(0,0);
}

// set the item numbers
void container::set(int heal_n, int mw_n)
{
    numOfHeal=heal_n;
    numOfMW=mw_n;
}

// get the number of heal
int container::nOfHeal()
{
    return numOfHeal;
}

// get the number of magic water
int container::nOfMW()
{
    return numOfMW;
}

// display the items;
void container::display()
{
    cout<<"Your bag contains: "<<endl;
    cout<<"Heal(HP+100): "<<numOfHeal<<endl;
    cout<<"Magic Water (MP+80): "<<numOfMW<<endl;
}

//use heal
bool container::useHeal()
{
    numOfHeal--;
    return 1;        // use heal successfully
}

//use magic water
bool container::useMW()
{
    numOfMW--;
    return 1;        // use magic water successfully
}

//=======================
//        player.h
//=======================

// The base class of player
// including the general properties and methods related to a character

#ifndef _PLAYER
#define _PLAYER
#include<string>
#include <iomanip>        // use for setting field width
#include <time.h>        // use for generating random factor
#include "container.h"
using namespace std;
enum job {sw, ar, mg};    /* define 3 jobs by enumerate type
                               sword man, archer, mage */
class player
{
    friend void showinfo(player &p1, player &p2);
    friend class swordsman;

protected:
    int HP, HPmax, MP, MPmax, AP, DP, speed, EXP, LV;
    // General properties of all characters
    string name;    // character name
    job role;        /* character's job, one of swordman, archer and mage,
                       as defined by the enumerate type */
    container bag;    // character's inventory

public:
    virtual bool attack(player &p)=0;    // normal attack
    virtual bool specialatt(player &p)=0;    //special attack
    virtual void isLevelUp()=0;            // level up judgement
    /* Attention!
    These three methods are called "Pure virtual functions".
    They have only declaration, but no definition.
    The class with pure virtual functions are called "Abstract class", which can only be used to inherited, but not to constructor objects. 
    The detailed definition of these pure virtual functions will be given in subclasses. */

    void reFill();        // character's HP and MP resume
    bool death();        // report whether character is dead
    void isDead();        // check whether character is dead
    bool useHeal();        // consume heal, irrelevant to job
    bool useMW();        // consume magic water, irrelevant to job
    void transfer(player &p);    // possess opponent's items after victory
    void showRole();    // display character's job
    
private:
    bool playerdeath;            // whether character is dead, doesn't need to be accessed or inherited
};

#endif

//=======================
//        player.cpp
//=======================


// character's HP and MP resume
#include"player.h"
#include<iostream>
using namespace std;
using std::cout;
void player::reFill()
{
    HP=HPmax;        // HP and MP fully recovered
    MP=MPmax;
}

// report whether character is dead
bool player::death()
{
    return playerdeath;
}

// check whether character is dead
void player::isDead()
{
    if(HP<=0)        // HP less than 0, character is dead
    {
        cout<<name<<" is Dead." <<endl;
        system("pause");
        playerdeath=1;    // give the label of death value 1
    }
}

// consume heal, irrelevant to job
bool player::useHeal()
{
    if(bag.nOfHeal()>0)
    {
        HP=HP+100;
        if(HP>HPmax)        // HP cannot be larger than maximum value
            HP=HPmax;        // so assign it to HPmax, if necessary
        cout<<name<<" used Heal, HP increased by 100."<<endl;
        bag.useHeal();        // use heal
        system("pause");
        return 1;    // usage of heal succeed
    }
    else                // If no more heal in bag, cannot use
    {
        cout<<"Sorry, you don't have heal to use."<<endl;
        system("pause");
        return 0;    // usage of heal failed
    }
}

// consume magic water, irrelevant to job
bool player::useMW()
{
    if(bag.nOfMW()>0)
    {
        MP=MP+100;
        if(MP>MPmax)
            MP=MPmax;
        cout<<name<<" used Magic Water, MP increased by 100."<<endl;
        bag.useMW();
        system("pause");
        return 1;    // usage of magic water succeed
    }
    else
    {
        cout<<"Sorry, you don't have magic water to use."<<endl;
        system("pause");
        return 0;    // usage of magic water failed
    }
}

// possess opponent's items after victory
void player::transfer(player &p)
{
    cout<<name<<" got"<<p.bag.nOfHeal()<<" Heal, and "<<p.bag.nOfMW()<<" Magic Water."<<endl;
    system("pause");
    bag.set( bag.nOfHeal(), bag.nOfHeal());
    // set the character's bag, get opponent's items
}

// display character's job
void player::showRole()
{
    switch(role)
    {
    case sw:
        cout<<"Swordsman";
        break;
    case ar:
        cout<<"Archer";
        break;
    case mg:
        cout<<"Mage";
        break;
    default:
        break;
    }
}


// display character's job
void showinfo(player &p1, player &p2)
{
    system("cls");
    cout<<"##############################################################"<<endl;
    cout<<"# Player"<<setw(10)<<p1.name<<"   LV. "<<setw(3) <<p1.LV
        <<"  # Opponent"<<setw(10)<<p2.name<<"   LV. "<<setw(3) <<p2.LV<<" #"<<endl;
    cout<<"# HP "<<setw(3)<<(p1.HP<=999?p1.HP:999)<<'/'<<setw(3)<<(p1.HPmax<=999?p1.HPmax:999)
        <<" | MP "<<setw(3)<<(p1.MP<=999?p1.MP:999)<<'/'<<setw(3)<<(p1.MPmax<=999?p1.MPmax:999)
        <<"     # HP "<<setw(3)<<(p2.HP<=999?p2.HP:999)<<'/'<<setw(3)<<(p2.HPmax<=999?p2.HPmax:999)
        <<" | MP "<<setw(3)<<(p2.MP<=999?p2.MP:999)<<'/'<<setw(3)<<(p2.MPmax<=999?p2.MPmax:999)<<"      #"<<endl;
    cout<<"# AP "<<setw(3)<<(p1.AP<=999?p1.AP:999)
        <<" | DP "<<setw(3)<<(p1.DP<=999?p1.DP:999)
        <<" | speed "<<setw(3)<<(p1.speed<=999?p1.speed:999)
        <<" # AP "<<setw(3)<<(p2.AP<=999?p2.AP:999)
        <<" | DP "<<setw(3)<<(p2.DP<=999?p2.DP:999)
        <<" | speed "<<setw(3)<<(p2.speed<=999?p2.speed:999)<<"  #"<<endl;
    cout<<"# EXP"<<setw(7)<<p1.EXP<<" Job: "<<setw(7);
    p1.showRole();
    cout<<"   # EXP"<<setw(7)<<p2.EXP<<" Job: "<<setw(7);
    p2.showRole();
    cout<<"    #"<<endl;
    cout<<"--------------------------------------------------------------"<<endl;
    p1.bag.display();
    cout<<"##############################################################"<<endl;
}

//=======================
//        swordsman.h
//=======================

// Derived from base class player
// For the job Swordsman
#ifndef _SWORDSMAN
#define _SWORDSMAN
#include "player.h"
#include<string>
using namespace std;
class swordsman :public player        // subclass swordsman publicly inherited from base player
{
public:
    swordsman(int lv_in=1, string name_in="Not Given");    
        // constructor with default level of 1 and name of "Not given"
    void isLevelUp();
    bool attack (player &p);
    bool specialatt(player &p);
        /* These three are derived from the pure virtual functions of base class
           The definition of them will be given in this subclass. */
    void AI(player &p);                // Computer opponent
};
#endif

//=======================
//        swordsman.cpp
//=======================

// constructor. default values don't need to be repeated here
#include"swordsman.h"
#include<iostream>
using namespace std;
swordsman::swordsman(int lv_in, string name_in)
{
    role=sw;    // enumerate type of job
    LV=lv_in;
    name=name_in;
    
    // Initialising the character's properties, based on his level
    HPmax=150+8*(LV-1);        // HP increases 8 point2 per level
    HP=HPmax;
    MPmax=75+2*(LV-1);        // MP increases 2 points per level
    MP=MPmax;
    AP=25+4*(LV-1);            // AP increases 4 points per level
    DP=25+4*(LV-1);            // DP increases 4 points per level
    speed=25+2*(LV-1);        // speed increases 2 points per level
    
    playerdeath=0;
    EXP=LV*LV*75;
    bag.set(lv_in, lv_in);
}

void swordsman::isLevelUp()
{
    if(EXP>=LV*LV*75)
    {
        LV++;
        AP+=4;
        DP+=4;
        HPmax+=8;
        MPmax+=2;
        speed+=2;
        cout<<name<<" Level UP!"<<endl;
        cout<<"HP improved 8 points to "<<HPmax<<endl;
        cout<<"MP improved 2 points to "<<MPmax<<endl;
        cout<<"Speed improved 2 points to "<<speed<<endl;
        cout<<"AP improved 4 points to "<<AP<<endl;
        cout<<"DP improved 5 points to "<<DP<<endl;
        system("pause");
        isLevelUp();    // recursively call this function, so the character can level up multiple times if got enough exp
    }
}

bool swordsman::attack(player &p)
{
    double HPtemp=0;        // opponent's HP decrement
    double EXPtemp=0;        // player obtained exp
    double hit=1;            // attach factor, probably give critical attack
    srand((unsigned)time(NULL));        // generating random seed based on system time

    // If speed greater than opponent, you have some possibility to do double attack
    if ((speed>p.speed) && (rand()%100<(speed-p.speed)))        // rand()%100 means generates a number no greater than 100
    {
        HPtemp=(int)((1.0*AP/p.DP)*AP*5/(rand()%4+10));        // opponent's HP decrement calculated based their AP/DP, and uncertain chance
        cout<<name<<"'s quick strike hit "<<p.name<<", "<<p.name<<"'s HP decreased "<<HPtemp<<endl;
        p.HP=int(p.HP-HPtemp);
        EXPtemp=(int)(HPtemp*1.2);
    }

    // If speed smaller than opponent, the opponent has possibility to evade
    if ((speed<p.speed) && (rand()%50<1))
    {
        cout<<name<<"'s attack has been evaded by "<<p.name<<endl;
        system("pause");
        return 1;
    }

    // 10% chance give critical attack
    if (rand()%100<=10)
    {
        hit=1.5;
        cout<<"Critical attack: ";
    }

    // Normal attack
    HPtemp=(int)((1.0*AP/p.DP)*AP*5/(rand()%4+10));
    cout<<name<<" uses bash, "<<p.name<<"'s HP decreases "<<HPtemp<<endl;
    EXPtemp=(int)(EXPtemp+HPtemp*1.2);
    p.HP=(int)(p.HP-HPtemp);
    cout<<name<<" obtained "<<EXPtemp<<" experience."<<endl;
    EXP=(int)(EXP+EXPtemp);
    system("pause");
    return 1;        // Attack success
}

bool swordsman::specialatt(player &p)
{
    if(MP<40)
    {
        cout<<"You don't have enough magic points!"<<endl;
        system("pause");
        return 0;        // Attack failed
    }
    else
    {
        MP-=40;            // consume 40 MP to do special attack
        
        //10% chance opponent evades
        if(rand()%100<=10)
        {
            cout<<name<<"'s leap attack has been evaded by "<<p.name<<endl;
            system("pause");
            return 1;
        }
        
        double HPtemp=0;        
        double EXPtemp=0;        
        //double hit=1;            
        //srand(time(NULL));        
        HPtemp=(int)(AP*1.2+20);        // not related to opponent's DP
        EXPtemp=(int)(HPtemp*1.5);        // special attack provides more experience
        cout<<name<<" uses leap attack, "<<p.name<<"'s HP decreases "<<HPtemp<<endl;
        cout<<name<<" obtained "<<EXPtemp<<" experience."<<endl;
        p.HP=(int)(p.HP-HPtemp);
        EXP=(int)(EXP+EXPtemp);
        system("pause");
    }
    return 1;    // special attack succeed
}

// Computer opponent
void swordsman::AI(player &p)
{
    if ((HP<(int)((1.0*p.AP/DP)*p.AP*1.5))&&(HP+100<=1.1*HPmax)&&(bag.nOfHeal()>0)&&(HP>(int)((1.0*p.AP/DP)*p.AP*0.5)))
        // AI's HP cannot sustain 3 rounds && not too lavish && still has heal && won't be killed in next round
    {
        useHeal();
    }
    else
    {
        if(MP>=40 && HP>0.5*HPmax && rand()%100<=30)
            // AI has enough MP, it has 30% to make special attack
        {
            specialatt(p);
            p.isDead();        // check whether player is dead
        }
        else
        {
            if (MP<40 && HP>0.5*HPmax && bag.nOfMW())
                // Not enough MP && HP is safe && still has magic water
            {
                useMW();
            }
            else
            {
                attack(p);    // normal attack
                p.isDead();
            }
        }
    }
}

//=======================
//        main.cpp
//=======================

// main function for the RPG style game

#include <iostream>
#include <string>
using namespace std;

#include "swordsman.h"


int main()
{
    string tempName;
    bool success=0;        //flag for storing whether operation is successful
    cout <<"Please input player's name: ";
    cin >>tempName;        // get player's name from keyboard input
    player *human;        // use pointer of base class, convenience for polymorphism
    int tempJob;        // temp choice for job selection
    do
    {
        cout <<"Please choose a job: 1 Swordsman, 2 Archer, 3 Mage"<<endl;
        cin>>tempJob;
        system("cls");        // clear the screen
        switch(tempJob)
        {
        case 1:
            human=new swordsman(1,tempName);    // create the character with user inputted name and job
            success=1;        // operation succeed
            break;
        default:

            human = new swordsman(1, tempName);//接口


            break;                // In this case, success=0, character creation failed
        }
    }while(success!=1);        // so the loop will ask user to re-create a character

    int tempCom;            // temp command inputted by user
    int nOpp=0;                // the Nth opponent
    for(int i=1;nOpp<5;i+=2)    // i is opponent's level
    {
        nOpp++;
        system("cls");
        cout<<"STAGE" <<nOpp<<endl;
        cout<<"Your opponent, a Level "<<i<<" Swordsman."<<endl;
        system("pause");
        swordsman enemy(i, "Warrior");    // Initialise an opponent, level i, name "Junior"
        human->reFill();                // get HP/MP refill before start fight
        
        while(!human->death() && !enemy.death())    // no died
        {
            success=0;
            while (success!=1)
            {
                showinfo(*human,enemy);                // show fighter's information
                cout<<"Please give command: "<<endl;
                cout<<"1 Attack; 2 Special Attack; 3 Use Heal; 4 Use Magic Water; 0 Exit Game"<<endl;
                cin>>tempCom;
                switch(tempCom)
                {
                case 0:
                    cout<<"Are you sure to exit? Y/N"<<endl;
                    char temp;
                    cin>>temp;
                    if(temp=='Y'||temp=='y')
                        return 0;
                    else
                        break;
                case 1:
                    success=human->attack(enemy);
                    human->isLevelUp();
                    enemy.isDead();
                    break;
                case 2:
                    success=human->specialatt(enemy);
                    human->isLevelUp();
                    enemy.isDead();
                    break;
                case 3:
                    success=human->useHeal();
                    break;
                case 4:
                    success=human->useMW();
                    break;
                default:
                    break;
                }
            }
            if(!enemy.death())        // If AI still alive
                enemy.AI(*human);
            else                            // AI died
            {
                cout<<"YOU WIN"<<endl;
                human->transfer(enemy);        // player got all AI's items
            }
            if (human->death())
            {
                system("cls");
                cout<<endl<<setw(50)<<"GAME OVER"<<endl;
                cout << "YOU DIED" << endl;
                cout << "KEEP TOUR DETERMINATION." << endl;// player is dead, program is getting to its end, what should we do here?
                system("pause");
                return 0;
            }
        }
    }
    cout << "THE END" << endl;        // You win, program is getting to its end, what should we do here?
    system("cls");
    cout<<"Congratulations! You defeated all opponents!!"<<endl;
    system("pause");
    return 0;
}

 

//后面截图就不放了

实验总结

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1.使用虚基类可以提供给派生类一个统一的接口，在现实中（比如RPG）有非常多的使用。

2.感觉再完善一下RPG就是上个世纪80年代的PC文字冒险游戏了，可以继续加入存档的功能。

评论

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a