public class Fibonacci3 {

    static int numCalls;

    public static void main (String[] argv)
    {
        // Test case 1:
        int n = 5;
        numCalls = 0;
        int f = fibonacci (n);
        System.out.println ("f(" + n + ") = " + f + "    numCalls=" + numCalls);

        // Test case 2:
        n = 20;
        numCalls = 0;
        f = fibonacci (n);
        System.out.println ("f(" + n + ") = " + f + "    numCalls=" + numCalls);
    }

    static int fibonacci (int n)
    {
        // We are recording the number of times this method is called.
        numCalls ++;
        
        if (n <= 2) {
            return (n-1);
        }
        
        return ( fibonacci(n-1) + fibonacci(n-2) );
    }

}