a006. 一元二次方程式 | From: [118.171.192.42] | 發表日期 : 2015-06-30 20:59

import java.util.Scanner; 

public class text3 {

    

    public static void main(String[] args) {

    Scanner sever = new Scanner(System.in);

    while (sever.hasNext())

    {

         int a = sever.nextInt();

      int b = sever.nextInt();

      int c = sever.nextInt();

      if (a>0 && (b^2-4*a*c) >=0)

      {

      Double x = (-b+Math.sqrt(b*b-4*a*c))/(2*a);

      Double y = (-b-Math.sqrt(b*b-4*a*c))/(2*a);

     

      String sx = Double.toString(x);

      String sy = Double.toString(y);

      //System.out.println(sx);

      //System.out.println(sx.subSequence(1, 3));

      //System.out.println(sx.subSequence(0, sx.length()-2));

      //System.out.println(sx.length());

      if (x == 0)

      {

      System.out.println("Two same roots x=" + sx.subSequence(0, sx.length()-2));

      }

      else

      {

      if(x>y)

      {

      System.out.println("Two different roots x1=" + sx.subSequence(0, sx.length()-2) + " , x2=" + sy.subSequence(0, sy.length()-2));

      }

      else

      {

      System.out.println("Two different roots x1=" + sy.subSequence(0, sy.length()-2) + " , x2=" + sx.subSequence(0, sx.length()-2));

      }

      }

      }

      else

      {

      System.out.println("No real root");      

      }

    }

    }

}