int iItem double dSubtotal double dSalesTax double dTotal do

int iItem;
    double dSubtotal;
    double dSalesTax;
    double dTotal;
    double dCost;
   // Instantiations:
   Scanner cin = new Scanner(System.in);
   DecimalFormat dfCurrency= new DecimalFormat(\"$#.00\");
    dSubtotal=0;
    iItem=1;
    dSalesTax =1;
    System.out.print(\"Enter item \"+iItem+ \" cost:\");
    dCost=cin.nextDouble();
    while(iItem!=-1)
    {
     dCost=cin.nextDouble();

     if(iItem!=-1)
     {
      dSubtotal= dSubtotal+dCost;
      iItem++;
     }
    }
    if(iItem>0)
     dSalesTax=dSubtotal*0.06;
      dTotal =dSubtotal+dSalesTax;
  
    // PROCESSING AND CALCULATIONS
    System.out.println(\"Subtotal: \"+dfCurrency.format(dSubtotal));
    System.out.println(\"Sales tax: \" +dfCurrency.format(dSalesTax));
    System.out.println(\"Total: \" +dfCurrency.format(dTotal));
}

Please help

Recode the previous problem so it can handle any number of items. Base your code on a sentinel-controlled while loop that will terminate the data entry phase when a negative cost is input by the user. Example input dialog follows. Yellow highlight is example end-user input:

One or more item costs entered by the user:

Enter item 1 cost: 14.25
Enter item 2 cost: 50.75
Enter item 3 cost: 10.00

Enter item 4 cost: -1

Items: 3

Subtotal: $75.00

Sales Tax: $4.50

Total: $79.50

A negative cost (sentinel) is entered as the very first item by the user:

No items to process

Solution

Hi,

I have modified the code and highlighted the code changes below.

NumberOfItems.java

import java.text.DecimalFormat;
import java.util.Scanner;

public class NumberOfItems {

  
   public static void main(String[] args) {
       int iItem;
   double dSubtotal;
   double dSalesTax;
   double dTotal;
   double dCost=0;
   // Instantiations:
   Scanner cin = new Scanner(System.in);
   DecimalFormat dfCurrency= new DecimalFormat(\"$#.00\");
   dSubtotal=0;
   iItem=1;
   dSalesTax =1;
   while(dCost!=-1)
   {

       System.out.print(\"Enter item \"+iItem+ \" cost:\");
       dCost=cin.nextDouble();
     
   if(dCost!=-1)
   {
   dSubtotal= dSubtotal+dCost;
   iItem++;
   }
   }
   if(iItem>0)
   dSalesTax=dSubtotal*0.06;
   dTotal =dSubtotal+dSalesTax;
  
   // PROCESSING AND CALCULATIONS
   if(dSubtotal != 0){
   System.out.println(\"Subtotal: \"+dfCurrency.format(dSubtotal));
   System.out.println(\"Sales tax: \" +dfCurrency.format(dSalesTax));
   System.out.println(\"Total: \" +dfCurrency.format(dTotal));
   }
   else{
       System.out.println(\"No items to process\");
   }

   }

}

Output:

Enter item 1 cost:14.25
Enter item 2 cost:50.75
Enter item 3 cost:10.00
Enter item 4 cost:-1
Subtotal: $75.00
Sales tax: $4.50
Total: $79.50

Enter item 1 cost:-1
No items to process