import java.util.Scanner;

public class Main {

 public static void main(String[] args) {

  Scanner scanner = new Scanner(System.in);

  System.out.println("请输入上次考试成绩：");

  double grade1 = scanner.nextDouble();

  System.out.println("请输入这次考试成绩：");

  double grade2 = scanner.nextDouble();

  System.out.printf("您的成绩提升了  %.2f %%", 100 * (grade2 - grade1) / grade1);

 }

}