题解 | #牛牛学说话之-浮点数#

import java.util.Scanner;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void main(String[] args) {
        Scanner in  = new Scanner(System.in);
        Float ff = in.nextFloat();
       // System.out.println(String.format("%.3f",ff));
        //System.out.format("%.3f",ff);
        System.out.printf("%.3f",ff);
    }
}