피보나치 수열 n번째 항

Test.java

import java.util.Scanner;
public class Test {

 /**
  * @param args
  */
 public static void main(String[] args) {
  // TODO Auto-generated method stub
  Scanner scan = new Scanner(System.in);
  int i;
  System.out.println("입력:");
  i=scan.nextInt();
 
 
  Fibonacci fib = new Fibonacci();
  System.out.println("피보나치 수열");
  System.out.println("f"+ i + " : " + fib.fibR(i));
 
  
 }

}

Fibonacci.java


public class Fibonacci {

 public int fibR(int n)
 {
  int fn2,fn1,fn=n;
  if(n<0)
   return -1;
  if(n<=1)
   return n;
  else{
   fn2 = 0;
   fn1 = 1;
  }
  for(int i=2;i<=n;i++){
   fn = fn1 + fn2;
   fn2 = fn1;
   fn1= fn;
  }
  return fn;
 }
}