经典递归求斐波那契数列

public class Test3 {//4public static void main(String[] args){double n=30;f(n);System.out.println(f(n));}public  static  double f(double n) {if(n==1){return 1;}if(n==2){return f(n-1)+1;}return f(n-1)+f(n-2);}}