//This is a java program to find the solution to the linear equation in single variable
import java.util.Scanner;

public class LEquation
{
    public static void main(String args[])
    {
        String eqn = "";
        float ans = 0;
        float coeffSum = 0;
        float constSum = 0;
        float coeffx[] = new float[100];
        float[] constant = new float[100];
        Scanner in = new Scanner(System.in);
        System.out.println("Enter a linear equation\n");
        eqn = in.nextLine();
        eqn += "\n";
        // System.out.println(eqn);
        for (int i = 0, j = 0, k = 0; i < eqn.length() - 1;)
            {
                if (eqn.charAt(i + 1) == 'x' && i < eqn.indexOf("="))
                    {
                        if (i != 0 && eqn.charAt(i - 1) == '-')
                            {
                                String x = eqn.substring(i, i + 1);
                                if (x != "+" && x != "-")
                                    {
                                        int n = -(Integer.parseInt(x, 10));
                                        coeffx[j++] = n;
                                    }
                            }
                        else
                            {
                                String x = eqn.substring(i, i + 1);
                                if (x != "+" && x != "-")
                                    {
                                        int n = Integer.parseInt(x, 10);
                                        coeffx[j++] = n;
                                    }
                            }
                        i += 3;
                    }
                if (eqn.charAt(i + 1) == 'x' && i > eqn.indexOf("="))
                    {
                        if (eqn.charAt(i - 1) == '-')
                            {
                                String x = eqn.substring(i, i + 1);
                                if (x != "+" && x != "-")
                                    {
                                        int n = Integer.parseInt(x, 10);
                                        coeffx[j++] = n;
                                    }
                            }
                        else
                            {
                                String x = eqn.substring(i, i + 1);
                                if (x != "+" && x != "-")
                                    {
                                        int n = -(Integer.parseInt(x, 10));
                                        coeffx[j++] = n;
                                    }
                            }
                        i += 3;
                    }
                if (eqn.charAt(i + 1) != 'x' && i < eqn.indexOf("="))
                    {
                        if (eqn.charAt(i - 1) == '-')
                            {
                                String x = eqn.substring(i, i + 1);
                                if (x != "+" && x != "-")
                                    {
                                        int n = -(Integer.parseInt(x, 10));
                                        constant[k++] = n;
                                    }
                            }
                        else
                            {
                                String x = eqn.substring(i, i + 1);
                                if (x != "+" && x != "-")
                                    {
                                        int n = Integer.parseInt(x, 10);
                                        constant[k++] = n;
                                    }
                            }
                        i += 2;
                    }
                if (eqn.charAt(i + 1) != 'x' && i > eqn.indexOf("="))
                    {
                        if (eqn.charAt(i - 1) == '-')
                            {
                                String x = eqn.substring(i, i + 1);
                                if (x != "+" && x != "-")
                                    {
                                        int n = Integer.parseInt(x, 10);
                                        constant[k++] = n;
                                    }
                            }
                        else
                            {
                                String x = eqn.substring(i, i + 1);
                                if (x != "+" && x != "-")
                                    {
                                        int n = -(Integer.parseInt(x, 10));
                                        constant[k++] = n;
                                    }
                            }
                        i += 2;
                    }
            }
        for (int i = 0; i < coeffx.length; i++)
            coeffSum += coeffx[i];
        for (int i = 0; i < constant.length; i++)
            constSum += constant[i];
        ans = constSum / coeffSum;
        System.out.println("Value of x = " + (-ans));
        in.close();
    }

}

/*
Enter a linear equation

2x+5=4x+9
Value of x = -2.0