Fibo.java

import static java.lang.Math.pow;
import static java.lang.Math.sqrt;

/**
 *
 * @author yt646712
 */
public class Fibo {
    public static int FibonacciRecursive(int n){
        if (n > 2){
            return (FibonacciRecursive(n-1) + FibonacciRecursive(n-2));
        }
        else{
            if (n == 0){
                return 0;
            }
            else{
                return 1;
            }
        }
    }
    
    public static int FibonacciIterative(int n){
        int a = 0; 
        int b = 1;
        
        //int totalC = 0;
        for (int i = 1; i < n; i++){

           int c = a+b;
           a = b;
           b = c;
        }
        return b;
    }
    
    public static double FibonacciNbOr(double n){
        double val = ((sqrt(5) / 5) *  pow(( (1 + sqrt(5)) / 2), n)-(sqrt(5) / 5) * pow(( (1 - sqrt(5)) / 2), n));
        return val;
    }
}