/*
 * Quadratic2014.java
 *
 * Created on 9 Οκτώβριος 2012, 9:12 πμ
 */


/**
 *
 *
 *MODULARITY - ADVANTAGES (reference to computational thinking)
 *(INSERT METHOD - CALCULATE METHOD - OUPUT METHOD)
 *1. MODULARITY ADDS TO THE READABILITY OF THE PROGRAM
 *2. EASIER TO TEST AND DEBUG
 *3. CODE REUSE - YOU CAN CALL THE SAME METHOD FROM DIFFERENT PARTS OF THE PROGRAM
 *4. DIFFERENT PARTS OF THE PROGRAM CAN BE DEVELOPPED FROM DIFFERENT PROGRAMERS AT THE SAME TIME - OFCOURSE 
 *   THEY MUST AGREE BETWEEN THEM INTO SOME CONVENTIONS LIKE SIZE OF THE MODULES, NAMES OF THE VARIABLES ETC
 *5. THE PROGRAM IS EASIER TO MAINTAIN AND UPGRADE   
 */
import java.io.*;
public class Quadratic2014 {
    
    double a, b, c, x1, x2, D;
    
    public Quadratic2014() throws IOException {
        insert();
        calculate();
        output();
    }
    
   public void insert()throws IOException {
       
       InputStreamReader inStream=new InputStreamReader(System.in);
        BufferedReader stdin=new BufferedReader(inStream);
        
        System.out.println("Solutions of the Quadratic ax^2 + bx + c = 0");
        System.out.print  ("Coefficient a ? = ");
        String data=stdin.readLine();
        a = Double.parseDouble(data);
        
        System.out.print  ("Coefficient b ? = ");
        data=stdin.readLine();
        b = Double.parseDouble(data);
        
        System.out.print  ("Coefficient c ? = ");
        data=stdin.readLine();
        c = Double.parseDouble(data);
   }
   
   public void calculate(){
       
       D = (b*b) - (4*a*c);
       
       if (D<0)
           System.out.println("D " + D + " is negative, no solution is possible");
       else
           if (D==0)
               x1=(-b)/(2*a);
           else
               {x1 = ((-b)+(Math.sqrt(D)))/(2*a);
                x2 = ((-b)-(Math.sqrt(D)))/(2*a);
               }     
   }
   
   public void output(){
       if (D==0)
           System.out.println("One double solution x1=x2="+x1);
       else
           if (D>0)
              System.out.println("Two separate solutions x1="+x1+" x2="+x2);
       
   }
   
   
    public static void main(String[] args) throws IOException {
        new Quadratic2014();
    }
    
}
// -------> write a program that calculates ax^3 + bx^2 +cx + d =0; capture all error cases.