java - 我的代码中的公式有什么问题？

Question

我们已经设置了一项任务来计算用户输入。我的代码可以编译，但是当我测试它时，我的退款输出始终为 0 :( 用户应在提示时输入他们的距离和自我贡献，但我的退款公式到底有什么问题？有人可以对此有所了解吗为了我？

 import java.util.*;
 public final class UserCalc {`
     public static void main(String[] args) {
         Scanner scanner = new Scanner(System. in );`
         System.out.print("Please enter the distance ");
         int distance = scanner.nextInt();
         System.out.print("Please enter the percentage of self contribution ");
         int selfcon = scanner.nextInt();
         int trainprice = (75 + (2 / 10)) * distance;
         int carprice = (26 + (7 / 10)) * distance;

         int refund = (Math.min(trainprice, carprice)) * ((100 - selfcon) / 100);

         System.out.print("You get a refund of " + refund + " pounds");
         int age = scanner.nextInt();
     }
 }

Answer 1

因为结果 of((100 - selfcon)/100)始终为零，并且您与您一起工作时integers应该使用floator double。

Answer 2

您使用的是整数运算而不是浮点运算，因此像 2/10 这样的表达式的计算结果为 0。

Answer 3

double distance = scanner.nextDouble();
System.out.print("Please enter the percentage of self contribution ");
double selfcon = scanner.nextDouble();
double trainprice = (75 + (2 / 10)) * distance;
double carprice = (26 + (7 / 10)) * distance;

doulbe refund = (Math.min(trainprice, carprice)) * ((100 - selfcon) / 100);

System.out.print("You get a refund of " + refund + " pounds");
int age = scanner.nextInt();