findFibonacciNumber

package practice;

/**
 * Fibonacci: 0, 1, 1, 2, 3, 5, 8, 13... 
 * n:         1, 2, 3, 4, 5, 6 Input an number n.
 * Output the Fibonacci number with that position
 */
public class FibonacciFinder {

	public static void main(String[] args) {
		System.out.println("Fibonacci at position -1: " + findFibonacciNumber(-1));
		System.out.println("Fibonacci at position 0: " + findFibonacciNumber(0));
		System.out.println("Fibonacci at position 3: " + findFibonacciNumber(3));
		System.out.println("Fibonacci at position 6: " + findFibonacciNumber(6));

	}

	public static Integer findFibonacciNumber(int n) {
		if (n <= 0) {
			System.out.println("Please input a positive interger number");
			return null;
		}
		if (n == 1)
			return 0;
		if(n==2)
			return 1;
		return findFibonacciNumber(n - 1) + findFibonacciNumber(n - 2);
	}
}