04. Clever Lily

import java.util.Scanner;

public class CleverLily {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int age = Integer.parseInt(scanner.nextLine());
        double machinePrice = Double.parseDouble(scanner.nextLine());
        double toyPrice = Double.parseDouble(scanner.nextLine());

        double sum = 0;
        int toy = 0, birthday = 10;

        for (int i = 1; i <= age; i++) {
            if (i % 2 == 0) {
                sum += birthday - 1;
                birthday += 10;
            } else {
                toy++;
            }
        }

        sum += toy * toyPrice;

        if (sum >= machinePrice) {
            System.out.printf("Yes! %.2f\n", sum - machinePrice);
        } else {
            System.out.printf("No! %.2f\n", machinePrice - sum);
        }
    }
}

ИЛИ:

import java.util.Scanner;

public class CleverLily {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int age = Integer.parseInt(scanner.nextLine());
        double machinePrice = Double.parseDouble(scanner.nextLine());
        double toyPrice = Double.parseDouble(scanner.nextLine());

        double sum = 0;
        int toy = 0, birthday = 10;

        for (int i = 1; i <= age; i++) {
            if (i % 2 == 0) {
                sum += birthday - 1;
                birthday += 10;
            } else {
                toy++;
            }
        }

        sum += toy * toyPrice;

        System.out.printf(sum >= machinePrice ?"Yes! %.2f\n" : "No! %.2f\n", Math.abs(sum - machinePrice));
    }
}