GamesPark

    public static void main(String[] args) {
        // Define variables
        double a; // price for child card
        double b; // price for adult card

        int countA; // counter for child card
        int countB; // counter for adult card

        int x; // number of child cards to buy
        int y; // number of adult cards to buy

        Scanner in = new Scanner(System.in);

        // 1. set price for each card
        // a = 13.70;
        // b = 15.20;
        do {
            System.out.print("Enter price for child card: ");
            a = in.nextDouble();
        } while (a <=0);

        do {
            System.out.print("Enter price for adult card: ");
            b = in.nextDouble();
        } while (b <=0);

        // 2. initialize counters to zero
        countA = 0;
        countB = 0;

        // 3. get number of cards to buy
        System.out.print("Enter number of child cards: ");
        x = in.nextInt();
        System.out.print("Enter number of adult cards: ");
        y = in.nextInt();

        // 4. start a loop
        while (x > 0 || y > 0) {
            double total=0;
            if (x>0) {
                // 4.1 calculate total price
                total += x*a;
                // 4.3 update counters
                countA += x;
            }

            if (y>0) {
                // 4.1 calculate total price
                total += y*b;
                // 4.3 update counters
                countB += y;
            }

            // 4.2 show message
            System.out.println("Toatl price is: " + total);

            // next customer
            // 4.4 get new values for next customer
            System.out.print("Enter number of child cards: ");
            x = in.nextInt();
            System.out.print("Enter number of adult cards: ");
            y = in.nextInt();
        } // end of while

        // 5. print number of cards
        System.out.println("Toatl child cards is: " + countA);
        System.out.println("Toatl adult cards is: " + countB);

        // 6. calculate and show total
        System.out.println("Toatl money for this day is: " + (countA*a + countB*b));

        // close scanner
        in.close();
    }