// Fibonacci number
Fib(r) >< (int n)
| n == 0 => r~0
| n == 1 => r~1
| _ => (*L)Fib(cnt1)~(n-1), Fib(cnt2)~(n-2), Add(r,cnt2)~cnt1;


Fib(r)~38;
r;
free r;