C++ 为什么函数返回垃圾值？

以下是我的完整计划：

得分.h

#ifndef SCORE_H
#define SCORE_H

class Score 
{

private:

    int* ipScore;
    float fAverage;
    int iSize;

public:

    Score();

    void enterScores();
    void calcAverage();
    void output();

    void setSize();
    int getSize();

    void setScore();
    int* getScore();

    float getAverage();
};

#endif

#ifndef CURVE1_H
#define CURVE1_H

#include "score.h"

class Curve1: public Score
{

public:

    Curve1();

    void curve();

};

#endif

得分.cpp

#include <iostream>

#include "score.h"

using namespace std;

Score::Score()
{
}

void Score::enterScores()
{
    cout << "How many test scores needed: ";

    setSize();

    cout << endl;

    setScore();

    for (int i = 0; i < getSize(); i++)
    {
        cout << "Enter score " << i + 1 << ": ";
        cin >> ipScore[i];
    }

    cout << endl;

}

void Score::calcAverage()
{
    fAverage = 0;

    for (int i = 0; i < getSize(); i++)
    {
        fAverage = fAverage + ipScore[i];
    }

    fAverage = fAverage / getSize();
}

void Score::output()
{
    int temp;

    for (int i = 0; i < getSize(); i++)
    {
        for (int j = 0; j < (getSize() - 1); j++)
        {
            if (ipScore[j] > ipScore[j + 1])
            {
                temp = ipScore[j];
                ipScore[j] = ipScore[j + 1];
                ipScore[j + 1] = temp;
            }
        }
    }

    cout << "Sorted list of data entered is:- " << endl;

    for (i = 0; i < getSize(); i++)
    {
        cout << "Score " << i + 1 << ": " << ipScore[i] << endl;
    }

    cout << endl;

    cout << "The average is: " << fAverage << endl;

    cout << endl;
}

void Score::setSize()
{
    cin >> iSize;
}

int Score::getSize()
{
    return iSize;
}

void Score::setScore()
{
    ipScore = new int[getSize()];
}

int* Score::getScore()
{
    return ipScore;
}

float Score::getAverage()
{
    return fAverage;
}

#include <iostream>

#include "curve1.h"

using namespace std;

Curve1::Curve1(): Score()
{
    cout << "Size was: " << getSize() << endl;
}

void Curve1::curve()
{
    cout << "Average score was: " << getAverage() << endl;  
}

#include <iostream>

#include "curve1.h"

using namespace std;

int main()
{
    Score scoreObj;
    Curve1 curve1Obj;

    scoreObj.enterScores();

    scoreObj.calcAverage();

    scoreObj.output();

    curve1Obj.curve();

    return 0;
}

曲线1.cpp

#include <iostream>

#include "score.h"

using namespace std;

Score::Score()
{
}

void Score::enterScores()
{
    cout << "How many test scores needed: ";

    setSize();

    cout << endl;

    setScore();

    for (int i = 0; i < getSize(); i++)
    {
        cout << "Enter score " << i + 1 << ": ";
        cin >> ipScore[i];
    }

    cout << endl;

}

void Score::calcAverage()
{
    fAverage = 0;

    for (int i = 0; i < getSize(); i++)
    {
        fAverage = fAverage + ipScore[i];
    }

    fAverage = fAverage / getSize();
}

void Score::output()
{
    int temp;

    for (int i = 0; i < getSize(); i++)
    {
        for (int j = 0; j < (getSize() - 1); j++)
        {
            if (ipScore[j] > ipScore[j + 1])
            {
                temp = ipScore[j];
                ipScore[j] = ipScore[j + 1];
                ipScore[j + 1] = temp;
            }
        }
    }

    cout << "Sorted list of data entered is:- " << endl;

    for (i = 0; i < getSize(); i++)
    {
        cout << "Score " << i + 1 << ": " << ipScore[i] << endl;
    }

    cout << endl;

    cout << "The average is: " << fAverage << endl;

    cout << endl;
}

void Score::setSize()
{
    cin >> iSize;
}

int Score::getSize()
{
    return iSize;
}

void Score::setScore()
{
    ipScore = new int[getSize()];
}

int* Score::getScore()
{
    return ipScore;
}

float Score::getAverage()
{
    return fAverage;
}

#include <iostream>

#include "curve1.h"

using namespace std;

Curve1::Curve1(): Score()
{
    cout << "Size was: " << getSize() << endl;
}

void Curve1::curve()
{
    cout << "Average score was: " << getAverage() << endl;  
}

#include <iostream>

#include "curve1.h"

using namespace std;

int main()
{
    Score scoreObj;
    Curve1 curve1Obj;

    scoreObj.enterScores();

    scoreObj.calcAverage();

    scoreObj.output();

    curve1Obj.curve();

    return 0;
}

#包括
#包括“曲线1.h”
使用名称空间std；
曲线1:：曲线1（）：分数（）
{
你似乎把类和类的实例搞混了

说你有

// This just defines a class. It does not create any instances of the class.
struct A
{
   A() : aVal(0) {}
   int aVal;
};

void foo()
{
   A a1; // Create instance of the class
   A a2; // Create another instance of the class.

   std::cout << a1.aVal << std::endl;  // 0
   std::cout << a2.aVal << std::endl;  // 0

   // Change the value of one instance.
   // It does not change the value of the other instance.
   a1.aVal = 10;
   std::cout << a1.aVal << std::endl;  // 10
   std::cout << a2.aVal << std::endl;  // still 0

   // Now change the value of the second instance.
   // Value of the first instance remains unchanged.
   a2.aVal = 20;
   std::cout << a1.aVal << std::endl;  // Still 10
   std::cout << a2.aVal << std::endl;  // 20
}

在代码中创建
Score
、
scoreObj
的实例和
Curve1
、
curve1Obj
的实例。
scoreObj
和
curve1Obj
的数据是独立的。修改
scoreObj
的数据不会更改
curve1Obj
的数据，反之亦然

希望这能让您明白一点。
在我的程序中，实际的问题是创建
Curve1
实例的
curve1Obj
将导致创建另一组带有默认值的
iSize
和
fAverage
，即垃圾值。
以前的
iSize
和
fAverage
的值是由
scoreObj
定义的，不能通过
curve1Obj
访问。所以我发现没有必要使用
scoreObj
，因为任何东西都可以通过
curve1Obj
访问。感谢你们的贡献。
它们是两个不同的对象？是的Curve1对象是
curve1Obj
，Score对象是
scoreObj
。因为它们是继承的……也许？？这并不意味着
Curve1
类型的对象知道你对
Score
类型的对象所做的任何事情。只有
Curve1
从
Score继承某些函数和变量ode>。我不知道我是否错了，但是
fAverage
和
iSize
中的值不是已经设置好了吗？Curve1只是调用
getAverage
和
getSize
来输出已经设置好的值吗？对象在其中扮演什么角色？对我来说，该对象只是调用
curve
函数，调用e
getSize
和
getAverage
。如果我错了，请告诉我。@R Sahu谢谢你的帮助。我知道我做错了什么。@SilverFalcon我很高兴我能帮上忙。