// Java Program to find root of a function, f(x)
import java.io.*;
import static java.lang.Math.*;

class Muller
{
    static final int MAX_ITERATIONS = 10000;

    // function to calculate f(x)
    static double f(double x)
    {
        // Taking f(x) = x ^ 3 + 2x ^ 2 + 10x - 20
        return 1*pow(x, 3) + 2*x*x + 10*x - 20;
    }

    static void Muller(double a, double b, double c)
    {
        int i;
        double res;

        for (i = 0;; ++i)
        {
            // Calculating various constants required
            // to calculate x3
            double f1 = f(a);
            double f2 = f(b);
            double f3 = f(c);
            double d1 = f1 - f3;
            double d2 = f2 - f3;
            double h1 = a - c;
            double h2 = b - c;
            double a0 = f3;
            double a1 = (((d2*pow(h1, 2)) - (d1*pow(h2, 2)))
                        / ((h1*h2) * (h1-h2)));
            double a2 = (((d1*h2) - (d2*h1))/((h1*h2) * (h1-h2)));
            double x = ((-2*a0)/(a1 + abs(sqrt(a1*a1-4*a0*a2))));
            double y = ((-2*a0)/(a1-abs(sqrt(a1*a1-4*a0*a2))));

            // Taking the root which is closer to x2
            if (x >= y)
                res = x + c;
            else
                res = y + c;

            // checking for resemblance of x3 with x2 till
            // two decimal places
            double m = res*100;
            double n = c*100;
            m = floor(m);
            n = floor(n);
            if (m == n)
                break;
            a = b;
            b = c;
            c = res;
            if (i > MAX_ITERATIONS)
            {
                System.out.println("Root cannot be found using" +
                                " Muller's method");
                break;
            }
        }
        if (i <= MAX_ITERATIONS)
            System.out.println("The value of the root is " + res);
    }

    // Driver main function
    public static void main(String args[])
    {
        double a = 0, b = 1, c = 2;
        Muller(a, b, c);
    }
}