Template Practice (Fabonicci Series)

#include <iostream.h>
template <class t>
class fs
{
public:
void fab()
{
    t a=0;
    t b=1;
    t c=0;
    t numbers = 0;
    t counter = 1;
    cout << "How many Fibonacci number you need ? : " ;
    cin >> numbers;
    do {
        counter++;
        c=a+b;
        cout<<"\t"<<c;
        a=b;
        b=c;   
    } while (counter <= numbers);
    cout << endl;  
}
};
void main()
{
fs <int> a;
a.fab();
}