import java.util.Scanner;

public class Main {

    public static void main(String[] args) {

        Scanner scanner = new Scanner(System.in);

System.out.print("输入上次考试成绩");

int score1 = scanner.nextInt();

System.out.print ("输入本次考试成绩");

int score2 = scanner.nextInt();

float a ;

a = (float)(score2-score1)/score1;

        System.out.printf("成绩提高的百分比为%.2f%%", a);

    }

}