C++ Program to concept of copy constructor

Program - 

#include<iostream.h>

#include<conio.h>

class abc

{

private:

int a;

float b;

public:

abc(int x,float y)

{

a=x;

b=y;

}

abc(abc&m)

{

a=m.a;

b=m.b;

}

void write(void)

{

cout<<a<<endl;

cout<<b;

}

};

void main()

{

clrscr();

abc m(20,4.2);

abc m2(m);

abc m3=m;

m.write();

m2.write();

m3.write();

getch();

}

Output - 

20

4.220

4.220

4.2