class Fibonacci {
    Fibonacci(this) {
    }

    calc(this, n) {
        if (n <= 1) {
            return n;
        }
        a = 0;
        b = 1;
        for (i = 2; i <= n; i++) {
            temp = a + b;
            a = b;
            b = temp;
        }
        return b;
    }
}

print("Fibonacci Demo");
fib = new Fibonacci();

for (n = 0; n <= 10; n++) {
    result = fib.calc(n);
    print("fib(" + str(n) + ") =", result);
}