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这个答案有点奇怪

BNV 发布于 2010-12-03 22:00, 797 次点击
程序代码:
#include<iostream.h>

class Myclass
{
private:
    int A,B,C;
    static int sum;
public:
    Myclass(int a,int b,int c)
    {
        A=a;B=b;C=c;
        Myclass::sum=A+B+C;
    }
    void GetNumber();
    void GetSum();
};
void Myclass::GetNumber()
    {
        cout<<"A = "<<A<<"\tB = "<<B<<"\tC = "<<C<<endl;
    }
void Myclass::GetSum()
    {
    cout<<"sum = "<<Myclass::sum<<endl;
    }
int Myclass::sum=0;
void main()
{
    Myclass M(3,7,10),N(14,9,11);
    M.GetSum();
    N.GetSum();
}





为什么结果两个sum都是34
8 回复
#2
ljt2010-12-03 22:49
因为sum是静态的,他是属于类的,而不是某个对象所有
#3
南国利剑2010-12-03 23:17
同意楼上
#4
BNV2010-12-03 23:25
为什么不是20呢
#5
BNV2010-12-03 23:26
如果要用sum分别显示20和34要怎么改呀
#6
laoyang1032010-12-04 10:00
程序代码:
#include<iostream.h>

class Myclass
{
private:
    int A,B,C;
    int sum;
public:
    Myclass(int a,int b,int c)
    {
        sum=0;
        A=a;B=b;C=c;
        sum=A+B+C;
    }
    void GetNumber();
    void GetSum();
};
void Myclass::GetNumber()
    {
        cout<<"A = "<<A<<"\tB = "<<B<<"\tC = "<<C<<endl;
    }
void Myclass::GetSum()
    {
    cout<<"sum = "<<sum<<endl;
    }
void main()
{
    Myclass M(3,7,10),N(14,9,11);
    M.GetSum();
    N.GetSum();
}

不用静态成员就可以啦   很简单
#7
windofland2010-12-04 11:28
cout<<"A = "<<A<<"\tB = "<<B<<"\tC = "<<C<<endl;
请问一下这个语句的作用是什么?
#8
laoyang1032010-12-04 12:46
void Myclass::GetNumber()
    {
        cout<<"A = "<<A<<"\tB = "<<B<<"\tC = "<<C<<endl;
    }
输出当前对象的数据成员 a b c  的值啊
#9
海豚小默2010-12-04 22:16
程序代码:
#include<iostream.h>

class Myclass
{
private:
    int A,B,C;
    static int sum;
public:
    Myclass(int a,int b,int c)
    {
        A=a;B=b;C=c;
        Myclass::sum=A+B+C;
    }
    void GetNumber();
    void GetSum();
};
void Myclass::GetNumber()
    {
        cout<<"A = "<<A<<"\tB = "<<B<<"\tC = "<<C<<endl;
    }
void Myclass::GetSum()
    {
    cout<<"sum = "<<Myclass::sum<<endl;
    }
int Myclass::sum=0;
void main()
{
    Myclass M(3,7,10);
    M.GetSum();
    Myclass N(14,9,11);
    N.GetSum();
}

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