DoWhile Loop in C++

#include<iostream.h>
#include<conio.h>
main()
{
int i=0;
clrscr();

do
{
cout<<"\n"<<i;
i++;
}while(i<20);
i=0;

do
{
cout<<"\n"<<i;
i+=3;
}while(i<20);
getch();
}