上一题：有两个2行3列的矩阵a和b，重载运算符“+”使之能用于矩阵相加，求两个矩阵之和。
题目：在上述的基础上，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。

[C++] 纯文本查看 复制代码

#include <iostream.h>
//using namespace std;
class Matrix
 {public:
   Matrix();
   friend Matrix operator+(Matrix &,Matrix &);
   friend ostream& operator<<(ostream&,Matrix&);
   friend istream& operator>>(istream&,Matrix&);
  private:
   int mat[2][3];
 };
 
Matrix::Matrix()
{for(int i=0;i<2;i++)
  for(int j=0;j<3;j++)
   mat[i][j]=0;
}

Matrix operator+(Matrix &a,Matrix &b)
{Matrix c;
 for(int i=0;i<2;i++)
   for(int j=0;j<3;j++)
     {c.mat[i][j]=a.mat[i][j]+b.mat[i][j];
     }
 return c;
}

istream& operator>>(istream &in,Matrix &m)
{cout<<"input value of matrix:"<<endl;
 for(int i=0;i<2;i++)
  for(int j=0;j<3;j++)
   in>>m.mat[i][j];
 return in;
}

ostream& operator<<(ostream &out,Matrix &m)
{for (int i=0;i<2;i++)
  {for(int j=0;j<3;j++)
   {out<<m.mat[i][j]<<" ";}
    out<<endl;}
 return out;
}

int main()
{ Matrix a,b,c;
 cin>>a;
 cin>>b;
 cout<<endl<<"Matrix a:"<<endl<<a<<endl;
 cout<<endl<<"Matrix b:"<<endl<<b<<endl;
 c=a+b;
 cout<<endl<<"Matrix c = Matrix a + Matrix b :"<<endl<<c<<endl;
 return 0;
}

ios需要c++知识吗？