Dynamic Allocation & Copy Constructor

Program in C++ to Create a Matrix using Dynamic allocation and copying it to another object using copy constructor and deallocate the memory using ‘delete’ key word.

Program:

#include<iostream>

#include<new>                                    //Header file for new

using namespace std;

class Matrix

{

int m,n;

int**p;                                   //Pointer to pointer(which stores the address of another pointers)

 public:

 Matrix()           //dynamic constructor

{

 cout<<"Enter no of rows and columns:";

 cin>>m>>n;                                      // Dynamic Allocation

p=new int*[m];                                   //rows

for(int i=0;i<m;i++)

p[i]=new int[n];                                 //in each row no of columns

int i,j;

cout<<"Enter values for the matrix";

for(i=0;i<m;i++)

 {

 for(j=0;j<n;j++)

{

 cin>>p[i][j];

}

}

  }

Matrix(Matrix &u)     // copy constructor

{

m=u.m;

n=u.n;

p=new int*[m];

for(int i=0;i<m;i++)

 p[i]=new int[n];

int i,j;

for(i=0;i<m;i++)

 {

for(j=0;j<n;j++)

  {

p[i][j]=u.p[i][j];

  }

 }

}

void add(Matrix f1)

{

cout<<"Addition of above two matrices:";

int i,j;

for(i=0;i<m;i++)

  {

for(j=0;j<n;j++)

   {

  cout<<p[i][j]+f1.p[i][j]<<" ";        //Displayed added matrix directly

   }

cout<<"\n";

  }

delete(p);

delete(f1.p);

}

 void dis()

 {

cout<<"Matrix: \n";

int i,j;

for(i=0;i<m;i++)

 {

  for(j=0;j<n;j++)

   {

   cout<<p[i][j];

   }

  cout<<endl;

  }

 }

};

int main()

{

Matrix m1;                // first object which invokes dynamic constructor

cout<<"\nFirst Object copy is:\n";

m1.dis();

Matrix m2(m1);            // Second object is same copy of fiest object using copy constructor

cout<<"\nSecond Object copy is:\n";

m2.dis();

cout<<"\nAddition of Same copies is:\n";

m1.add(m2);

return 0;

}