import java.util.Scanner;
/**
 * This class calculates cost of several trips using while looop.
 */
public class SampleExam1Question5 {
  /**
   * main does all the work, no methods necessary.
   * put into a while loop:
   * 1. read in data
   * 2. compute base price
   * 3. use if to check for discount
   * 4. compute final price
   * Outside of loop: print total # of trips and nodiscount
   */
  public static void main(String[] args)  {
    
       Scanner sc = new Scanner(System.in);
       int idnum, miles, noDiscount=0, numTrips=0;
       double pricePerMile;
       idnum=sc.nextInt();
       while(idnum != -1) {
         numTrips++;
         // 1. read in data
         miles = sc.nextInt();
         pricePerMile = sc.nextDouble();
         // 2. compute base price
         double basePrice = miles*pricePerMile;
         System.out.printf("Base price for trip: %.2f.\n", basePrice);
         // 3. check for discount
         double discount=0;
         if (miles >= 20)  {
             discount = .075*basePrice;
             System.out.printf("you received a discount of %.2f.\n",discount);
         }
         else {
             System.out.println("You did not receive the discount.");
             noDiscount++;
         }
         // 4. compute final price
         double finalPrice = basePrice - discount;
         // 5. Repeat: use structure read loop
         System.out.print("Enter ID number of trip, -1 to exit: ");
         idnum = sc.nextInt();
       }// end while
         
       // 6. Print totals
       System.out.println("Total number of trips is: " + numTrips + 
                          " number of trips without a discount is: " 
                            + noDiscount);
  }
}