C++ language

#include<stdio.h>
class demo
{
private :
int x,y;
public :
int a,b;
void getdata();
void putdata();
};
void demo::getdata()
{
cout<<"\n Emnter the value of x and y";
cin>>x>>y;
cout<<"\n Enter the value of a and b";
cin>>a>>b;
}
void demo::putdata()
{
cout<<"\n Enter the value of x amd y";
cout<<"\n Enter the value of a and b";
}
void main()
{
demo d;
d.getdata();
cout<<"\n the entered values are";
d.putdata();
d.a=10;
d.b=20;
cout<<"\n The value after moderation are";
d.putdata();
}