здравейте!
някой има ли идея защо не работи(маркираното поле, което не знам дали излиза маркирано, но говоря за:  Math.abs(Math.ceil(timeLeft)))?
не би ли трябвало Math.ceil да закръгля към по–голямото?
изходът вместо 

Cleaning time: 0.76

No, there isn't a surprise - shortage of time -> 1 hours.

е

Cleaning time: 0.76
No, there isn't a surprise - shortage of time -> 0.0 hours.

import java.util.Scanner;

public class Main {

    public static void main(String[] args) {

        Scanner scanner = new Scanner(System.in);

        double A = Double.parseDouble(scanner.nextLine());
        double B = Double.parseDouble(scanner.nextLine());
        double C = Double.parseDouble(scanner.nextLine());
        double D = Double.parseDouble(scanner.nextLine());

        double cleaningTime = 1 / (1/A + 1/B + 1/C);
        double restTime = cleaningTime * 0.15;
        double allTime = restTime + cleaningTime;
        double timeLeft = D - allTime;

        if (timeLeft > 0){
            System.out.printf("Cleaning time: %.2f",allTime);
            System.out.printf("%n");
            System.out.println("Yes, there is a surprise - time left -> " +
            Math.floor(timeLeft) + " hours.");
        }else {
            System.out.printf("Cleaning time: %.2f",allTime);
            System.out.printf("%n");
            System.out.println("No, there isn't a surprise - shortage of time -> " +
            Math.abs(Math.ceil(timeLeft)) + " hours.");
        }
    }
}