Thread: Fibonacci numbers (using class)

i want to write a program to compute the Fibonacci numbers (max 20 numbers).but i want to do it using a class.

i wrote this and i want your opinions.
it computes the Fibonacci numbers for given num and then prints the result.
should i change anything?

Code:

class fib
{
    private:
        int fibar[20];
    public:
        fib();
        void create_nums(int);
        void show(int);
};
void fib::show(int n)
{
        for(int i=0;i<n;i++)
    cout<<fibar[i]<<"\n";
}
fib::fib()
{
    memset(fibar,0,sizeof(int)*20);
    fibar[1]=1;
}
void fib::create_nums(int n)
{
        for(int i=2;i<n;i++)
    fibar[i]=fibar[i-2]+fibar[i-1];
}
main()
{
    fib obj;
    int num;

    cout<<"give N:";
    do{
        cin>>num;
        }while(num>20 || num<0);

        obj.create_nums(num);
        obj.show(num);
}