4.cpp

#include <iostream> using namespace std;   class Matrix                        {    public:  Matrix(); friend Matrix operator+(Matrix &,Matrix &);         void input();                                void display();                   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; }   void Matrix::input()                                      { cout<<"input value of matrix:"<<endl;  for(int i=0;i<2;i++)      for(int j=0;j<3;j++)    cin>>mat[i][j];}  void Matrix::display()   {for (int i=0;i<2;i++) {for(int j=0;j<3;j++)     {cout<<mat[i][j]<<" ";}        cout<<endl;} }    int main() {Matrix a,b,c;  a.input();  b.input();   cout<<endl<<"Matrix a:"<<endl;   a.display();     cout<<endl<<"Matrix b:"<<endl;  b.display();    c=a+b;                               cout<<endl<<"Matrix c = Matrix a + Matrix b :"<<endl;  c.display();  return 0;}