解答：
package 测试;
import java.util.Scanner;
/**
* @author xcdq.SGS
* @date 2021/4/12 18:19
*/
public class demo4 {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
System.out.println("请输入是否是会员：是（y）/否（其他字符）");
String isy = input.next();
System.out.println("请输入购物金额");
int jine =input.nextInt();
double bazhe = jine*0.8;
double qiwuzhe = jine *0.75;
double jiuzhe = jine*0.9;
if (isy.equals("y")){
if (jine <200){
System.out.println("实际支付：" + bazhe);
}else if (jine>=200){
System.out.println("实际支付：" + qiwuzhe);
}
}
if (jine >100){
System.out.println("实际支付" + jiuzhe);
}else if (jine < 100){
System.out.println("实际支付：" + jine);
}
}
}
