研究了半天，终于闹明白答题格式

import java.io.BufferedInputStream;
import java.util.Scanner;
//请不要使用package，这将会导致您的代码不能通过测试
public class Test{
public static int getPerfectSquare(int a, int b) {
return (int) Math.floor(Math.sqrt(b)) - (int) Math.ceil(Math.sqrt(a))    + 1;
}
public static void main(String[] args)
{
Scanner cin = new Scanner(new BufferedInputStream(System.in));
while(cin.hasNext()){
int a = cin.nextInt();
int b = cin.nextInt();
System.out.println(getPerfectSquare(a,b));
}
cin.close();      }

}