import java.util.*;
import java.math.BigDecimal;
public class Main {
    public static void main(String[] args) {
        Scanner console = new Scanner(System.in);
        int price = console.nextInt();
        int cost = 0;

        //write your code here......
        if(price<100)
        cost=price;
        else if(price>=100&&price<500)
        cost=(int)(price*0.9);
        else if(price>=500&&price<2000)
        cost=(int)(price*0.8);
        else if(price>=200&&price<5000)
        cost=(int)(price*0.7);
        else cost=(int)(price*0.6);
        System.out.println(cost);
    }
}

if-else分支语句加强制类型转换,注意不打折的情况。