C++ OOP 学习

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Critter Caretaker 源码

#include <iostream>
using namespace std;
class Critter
{
public:
    Critter(int hunger = 0, int boredom = 0);
    void Talk();
    void Eat(int food = 4);
    void Play(int fun = 4);
    void GetStatus();
    int GetHunger() const;
    int GetBoredom() const;

private:
    int m_Hunger;
    int m_Boredom;
    int GetMood() const;
    void PassTime(int time = 1);
};

Critter::Critter(int hunger, int boredom) :
    m_Hunger(hunger),
    m_Boredom(boredom)
{}

inline int Critter::GetMood() const
{
    return (m_Hunger + m_Boredom);
}

void Critter::PassTime(int time)
{
    m_Hunger += time;
    m_Boredom += time;
}

void Critter::Talk()
{
    cout << "I'm a critter and I feel ";
    int mood = GetMood();

    if (mood > 15)
    {
        cout << "mad.\n";
    }
    else if (mood > 10)
    {
        cout << "frustrated.\n";
    }
    else if (mood > 5)
    {
        cout << "okay.\n";
    }
    else
    {
        cout << "happy.\n";
    }
    PassTime();
}

void Critter::Eat(int food)
{
    cout << "Brruppp.\n";
    m_Hunger -= food;
    if (m_Hunger < 0)
    {
        m_Hunger = 0;
    }
    PassTime();
}

void Critter::Play(int fun)
{
    cout << "Wheee!\n";
    m_Boredom -= fun;
    if (m_Boredom < 0)
    {
        m_Boredom = 0;
    }
    PassTime();
}

void Critter::GetStatus()
{
    cout << "Your critter's hunger:  " << m_Hunger << endl;
    cout << "Your critter's boredom: " << m_Boredom << endl;
    PassTime();
}

int Critter::GetHunger() const
{
    return m_Hunger;
}

int Critter::GetBoredom() const
{
    return m_Boredom;
}

int main()
{
    Critter crit;
    crit.Talk();
    int choice;
    do
    {
        cout << "\nCritter Caretaker\n\n";
        cout << "0 - Quit\n";
        cout << "1 - Listen to your critter\n";
        cout << "2 - Feed your critter\n";
        cout << "3 - Play with your critter\n";
        cout << "4 - Get critter's status\n\n";
        cout << "Choice: ";
        cin >> choice;
        switch (choice)
        {
        case 0:
            cout << "Good-bye.\n";
            break;
        case 1:
            crit.Talk();
            break;
        case 2:
            crit.Eat();
            break;
        case 3:
            crit.Play();
            break;
        case 4:
            crit.GetStatus();
            break;
        default:
            cout << "\nSorry, but " << choice << " isn't a valid choice.\n";
        }

        if (crit.GetHunger() >= 10)
        {
            cout << "\"I am close to dieeee!\"" << endl;
        }
        if (crit.GetBoredom() >= 15)
        {
            cout << "\"I am too unhappy to maintain myself!\"" << endl;
        }

        if (crit.GetHunger() >= 15 || crit.GetBoredom() >= 20)
        {
            cout << "\n\n Oh no! Your critter die! \n\n  --G--A--M--E-- --O--V--E--R-- \n\n";
            break;
        }

            cout << "------n-e-x-t----r-o-u-n-d------" << endl;
    } while (choice != 0);
    return 0;
}