第七章

7.12定义一个矩阵类Matrix，重载运算符“+”，使之能用于矩阵的加法运算。有两个矩阵a和b，均为2行4列。求两个矩阵之和。重载流插入运算符“<<”和流提取运算符“>>”，使之能用于该矩阵的输入和输出

#include<iostream>  
#include<iomanip>  
using namespace std;  
  
class Matrix{  
public:  
    Matrix() {}  
    ~Matrix(){}   
    Matrix operator +(Matrix &);   
        friend ostream& operator<<(ostream &output, Matrix &);    
    friend istream& operator>>(istream &input, Matrix &);   
private:  
    int m_[2][4];  
};  
  
Matrix Matrix::operator+(Matrix &m)          
{  
    Matrix m3;  
    for (int  i = 0; i < 2; i++)  
    {  
        for (int j = 0; j < 4; j++)  
            m3.m_[i][j] = m_[i][j] + m.m_[i][j];  
    }  
    return m3;  
}  
  
istream& operator>>(istream &input, Matrix &a)  
{  
    for (int  i = 0; i < 2; i++)  
    {  
        for (int j = 0; j < 4; j++)  
            cin >> a.m_[i][j];  
    }  
    cout << endl;  
    return input;  
}  
ostream& operator<<(ostream &output, Matrix &b)  
{  
     for (int i = 0; i < 2; i++)  
          {  
                for (int j = 0; j < 4; j++)  
             cout <<setw(4)<< b.m_[i][j];  
            cout << endl;  
      }  
    cout << endl;  
    return output;  
}  
  
int main()  
{  
    Matrix m1;  
    cout << "请输入m1矩阵" << endl;  
    cin >> m1;  
    cout << "m1矩阵如下：" << endl;  
    cout << m1;  
    Matrix m2;  
    cout << "请输入m2矩阵" << endl;  
    cin >> m2;  
    cout << "m2矩阵如下：" << endl;  
    cout << m2;  
    Matrix M;  
    cout << "m1矩阵和m2矩阵的和如下" << endl;  
    M = m1 + m2;  
    cout << M;      
      
  
        system("pause");  
    return 0;  
}