循环计算 - Java

Question

我无法根据购买的瓶子数量计算出客户支付的价格。对于购买的任何数量的瓶子，它总是返回14美元的价值。请参阅下面的Java代码：

// PriceCalculator class that calculates the prices for customers 
// counter controlled repetition 

import java.util.Scanner; // program uses class Scanner 

public class PriceCalculator 
{ 
private String beginSale; // name of shop this price is calculated 

// constructor initializes beginSale 
public PriceCalculator(String name) 
{ 
    beginSale = name; // initializes shopName 
} // end constructor 

// method to set the shop name 
public void setBeginSale (String name) 
{ 
    beginSale = name; // set the welcome address 
} // end method setBeginSale 

// method to retrieve the welcome address 
public String getBeginSale() 
{ 
    return beginSale; 
} // end method getBeginSale 

// display a welcome message to the shopper 
public void displayMessage() 
{ 
    // getBeginSale gets the thank you address 
    System.out.printf("Welcome to Price Calculator for Purchasing Wines at %s!\n", 
     getBeginSale()); 
} // end method displayMessage 

// determine charges based on 5 customers who shopped 
public void calculatePrice() 
{ 
    // create scanner to obtain input from command window 
    Scanner input = new Scanner(System.in); 

    int basePrice; // base price of a bottle of wine 
    String customer; // name of customer 
    int gradeCounter; // number of customers to be entered next 
    int bottles; // number of bottles purchased 
    double discount; // discount value on the number of bottles 
    double rate; 
    double total; // total costs of wine purchased 

    // initialization phase 
    basePrice = 10; // initialize base price 
    gradeCounter = 1; // initialize loop counter 
    bottles = 1; // initialize bottles 
    discount = (basePrice * bottles); // initialize discount 
    rate = 0; 
    customer = null; // initialize customer name 

    // processing phase uses counter-controlled repetition 
    while (gradeCounter <= 3) // loop 5 times 
    { 
     System.out.print("Enter the name for customer " + gradeCounter + " : "); // prompt 
     customer = input.next(); // input next name 
     System.out.print("Enter the number of bottles for customer " + gradeCounter + " : "); // prompt 
     bottles = input.nextInt(); // input next bottles sold 
     gradeCounter = gradeCounter + 1; // increment counter by 1 
     discount = (basePrice * bottles) - (rate * bottles); 

     System.out.printf("\nThe Price for Customer - %s is : $%.2f\n\n", 
      customer, discount); 
    } // end while loop 

    // calculate purchase based on number of bottles sold 

    if (bottles <= 6) 
    { 
     discount = (basePrice * bottles) - (rate * bottles); // calculates discount 
    } 
    else if 
    (bottles > 6 && bottles<= 12) 
     { 
     discount = (basePrice * bottles) - (rate * bottles); // calculates discount 
     } 
    else if (bottles > 48) 
     System.out.println ("It is forbidden to sell above the maximum range"); 

} // end method calculatePrice 
} // end class PriceCalculator 

Answer 1

很简单;您将在输入数据的循环中打印价格，以便价格不会发生变化，并且一次又一次地打印相同的语句。

只需推动以下语句：

System.out.printf("\nThe Price for Customer - %s is : $%.2f\n", customer, discount); 
} // end while loop 

后这一行：

System.out.println("It is forbidden to sell above the maximum range"); 

输出将是：

Welcome to Price Calculator for Purchasing Wines at Red Rocky! 
Enter the name for customer 1: asdfsa 
Enter the number of bottles for customer 1: 3 

The Price for Customer - asdfsa is : $42.00 
Enter the name for customer 1: gasdfs 
Enter the number of bottles for customer 1: 4 

The Price for Customer - gasdfs is : $56.00 
Enter the name for customer 1: asfasdf 
Enter the number of bottles for customer 1: 5 

The Price for Customer - asfasdf is : $70.00 

你也可以更换该声明

System.out.print("Enter the name for customer 1: "); 

与

System.out.print("Enter the name for customer " + gradeCounter + ":"); 

最终代码看起来像：

while (gradeCounter <= 3) // loop 3 times 
{ 
    System.out.print("Enter the name for customer 1: "); // prompt 
    customer = input.next(); // input next name 
    System.out.print("Enter the number of bottles for customer 1: "); // prompt 
    bottles = input.nextInt(); // input next bottles sold 
    gradeCounter = gradeCounter + 1; // increment counter by 1 
// calculate purchase based on number of bottles sold 
    if (bottles <= 6) { 
     discount = (basePrice * bottles); // calculates discount 
    } else if (bottles > 6 || bottles <= 12) { 
     discount = discount * 0.05 * bottles * basePrice; // calculates discount 
    } else if (bottles > 48) 
    System.out.println("It is forbidden to sell above the maximum range"); 
    System.out.printf("\nThe Price for Customer - %s is : $%.2f\n",customer, discount); 
} // end while loop 

Answer 2

你想改变你的

if (bottles > 6 || bottles <= 12) 

到

if (bottles > 6 && bottles <= 12) 

Answer 3

您没有更改任何值...首先，你设置折扣值：

discount = (basePrice * bottles); // initialize discount 

然后在while lo op，它从不根据给定的值更新：

System.out.printf("\nThe Price for Customer - %s is : $%.2f\n", 
     customer, discount); 

不应该在printf之前的while循环内设置折扣值吗？ :)

或者更明确：

// processing phase uses counter-controlled repetition 
while (gradeCounter <= 3) // loop 3 times 
{ 
    System.out.print("Enter the name for customer 1: "); // prompt 
    customer = input.next(); // input next name 
    System.out.print("Enter the number of bottles for customer 1: "); // prompt 
    bottles = input.nextInt(); // input next bottles sold 
    gradeCounter = gradeCounter + 1; // increment counter by 1 
discount = (basePrice * bottles); 
    System.out.printf("\nThe Price for Customer - %s is : $%.2f\n", 
     customer, discount); 
} // end while loop 

Answer 4

变化||到& &

if (bottles > 6 || bottles <= 12) // Your code 

if (bottles > 6 && bottles <= 12) // changes