爪哇，减去双数据类型

-1

我想做一个简单的计算。我无法弄清楚如何在最后的if-else语句中减去“double admissionPrice”。爪哇，减去双数据类型

其指向减号给我这个错误消息：运营商 - 不能用于为java.lang.String，双

请帮助。谢谢。

import java.text.*; 
import java.util.Scanner; 


class IMC { 
    public static void main(String[] args) { 

    int numEmployees = 0; 
    double costPerAttendee = 0.00; 
    int employeeDiscount; 
    double admissionPrice = 0.00; 

    Scanner keyboard = new Scanner (System.in); 

    System.out.print("Enter amount of employees attending: "); 
    numEmployees = keyboard.nextInt(); 

    System.out.print("Have any employees attended previously? \n For: YES=1 or NO=2" 
         ); 
    employeeDiscount = keyboard.nextInt(); 



    if (numEmployees == 1) { admissionPrice = 695.00; 


    } else if (numEmployees == 2 || numEmployees == 3 ||numEmployees == 4) { admissionPrice = 545.00; 


    } else if (numEmployees >= 5 ||numEmployees >= 6 ||numEmployees >= 7 ||numEmployees >= 8){ admissionPrice = 480.00; 


    } else if (numEmployees >= 9) { admissionPrice = 395.00; 

    } 

     System.out.print("The cost per attendee is: " + admissionPrice); 


    if (employeeDiscount == 1){ 
     System.out.print("Total price after discount (15%) is : " + admissionPrice - (admissionPrice * 0.15)); 

    } else if (employeeDiscount == 2) { 
      System.out.print("No discount. Total price is still: " + admissionPrice); 
    } 


    } 
}

来源

2013-02-04 montenegroxnj

你可以使用'（）'来避免'（admissionPrice - （admissionPrice * 0.15））'。 –

尝试将整个数值表达式放在圆括号中：'（admissionPrice - （admissionPrice * 0.15））' – pyon

我不明白这里的downvotes，对我没有任何意义。 –

System.out.print("Total price after discount (15%) is : " + (admissionPrice - (admissionPrice * 0.15))); 
                  ^         ^

您需要添加()固定的优先级，否则，作为错误指示，你减去，而不是从admissionPrice但毕竟是"To....:" + admissionPrice

来源

2013-02-04 02:02:28

谢谢！ @karthik t – montenegroxnj

将形成串圆括号(admissionPrice - (admissionPrice * 0.15))。现在，它在尝试减法之前将门票价格连接到"Total price after discount (15%) is : "。

来源

2013-02-04 02:02:42 brandonsbarber

非常感谢！这固定它 – montenegroxnj

您的println()声明中的+运算符优先并将admissionPrice转换为String。

将算术运算放在括号内。

来源

2013-02-04 02:02:49

哇没有看到一个..非常感谢 – montenegroxnj

爪哇，减去双数据类型

回答

相关问题