package com.company;

import java.util.Scanner;

class Variable {
    private double a;
    private double b;
    private double c;

    void input()
    {
        Scanner scan = new Scanner(System.in);
        a = Dialog.isEnteringValues(scan, "A");
        b = Dialog.isEnteringValues(scan, "B");
        c = Dialog.isEnteringValues(scan, "C");
    }

    void view()
    {
        Dialog.isEnteredValues(a, b, c);
    }

    void calculate()
    {
        double delta = b * b - 4 * a * c;
        Dialog.isDeltaResult(delta);

        if (delta < 0)
            Dialog.isNoSolution();

        else {
            if (delta == 0) {
                double x0 = -b / (2 * a);
                Dialog.isOneSolution(x0);
            }

            if (delta > 0) {
                double x1 = (-b - Math.sqrt(delta)) / 2 * a;
                double x2 = (-b + Math.sqrt(delta)) / 2 * a;
                Dialog.isTwoSolution(x1, x2);
            }
        }
    }
}


public class Dialog {

    static double isEnteringValues(Scanner scan, String str)
    {
        System.out.print("Wprowadź wartość liczby " + str + ": ");
        return scan.nextDouble();
    }

    static void isEnteredValues(double a, double b, double c)
    {
        System.out.println("A: " + a);
        System.out.println("B: " + b);
        System.out.println("C: " + c);
    }

    static void isDeltaResult(double delta)
    {
        System.out.println("D: " + delta);
    }

    static void isNoSolution()
    {
        System.out.println("Brak rozwiązania.");
    }

    static void isOneSolution(double x0)
    {
        System.out.println("x0: " + x0);
    }

    static void isTwoSolution(double x1, double x2)
    {
        System.out.println("x1: " + x1);
        System.out.println("x2: " + x2);
    }
}

public class Calculation {

    public static void main(String[] args) {
        Variable variable = new Variable();

        variable.input();
        variable.view();
        variable.calculate();
    }
}