Java 递归简 单

解题思路:

注意事项:

参考代码:

public static void main(String[] args) {

Scanner scanner = new Scanner(System.in);

int n =scanner.nextInt();

double sum=0;

double [] f = new double [200];

f[1]=2;

f[2]=3;

double [] t = new double [200];

t[1]=1;

t[2]=2;

for(int i=1;i<=n;i++) {

if(i<3) {

sum=sum+f[i]/t[i];

}else {

f[i]=f[i-1]+f[i-2];

t[i]=t[i-1]+t[i-2];

sum=sum+f[i]/t[i];

}

}

System.out.printf("%.2f",sum);

}