cara membuat segitiga tengahnya kosong

#include <iostream.h>
#include <conio.h>

int main()
{
int i, j, tinggi;

cout<<("input : ");
cin>>tinggi;

for(i = 2; i <= tinggi; i++) {
cout<<"";
for(j =1; j <= tinggi - i; j++) {
cout<<" ";
}

for(j =1; j <= i; j++) {
cout<<"*";
for(j=3;j<=i;j++){
cout<<" ";
}
}

for(j =2; j <= i-1; j++) {

for(j=3;j<=i-1;j++){
cout<<" ";
}
cout<<"*";
}

cout<<"\n";

}
cout<<"*";
for(i=2;i<=tinggi;i++)
{
cout<<"*";
cout<<"*";
}
getch();

}