конвертироватие переменной double

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
public class Main {
public static void main(String[] args)throws IOException{
        BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
        final double x, y, z;
        System.out.print("Введите X: ");
        x = Integer.parseInt(in.readLine());
        System.out.print("Введите Y: ");
        y = Integer.parseInt(in.readLine());
        System.out.print("Введите Z: ");
        z = Integer.parseInt(in.readLine());
        final double kvadrat = 2;
        final double f = y - x;
        final double a = y + z;
        final double h = y - x;
        final double l = a / h;
        final double k = 1 + (y - (int) Math.pow(x, kvadrat));
        final double m = l / k;
        final double n = f * m;
        System.out.println("fi= " + Integer.toString((int) +n));
    }
}

String.valueOf(double_variable)

System.out.println("fi= " + n);

public class Main {
public static void main(String[] args){
final double x=1.825,y=18.225,z=3.298;
final double kvadrat=2;
final double f=y-x;
final double a=y+z;
final double h=y-x;
final double l=a/h;
final double k=1+(y-(int)Math.pow(x, kvadrat));
final double m=l/k;
final double n=f*m;
System.out.println("fi= " +n);
 }
}

x = Double.parseDouble(in.readLine());

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
public class Main {
public static void main(String[] args)throws IOException{
        BufferedReader vvod = new BufferedReader(new InputStreamReader(System.in));
        final double x, y, z, kvadrat = 2;
        System.out.print("Введите X: ");
        x = Double.parseDouble(vvod.readLine());
        System.out.print("Введите Y: ");
        y = Double.parseDouble(vvod.readLine());
        System.out.print("Введите Z: ");
        z = Double.parseDouble(vvod.readLine());
        final double f = y - x;
        final double a = y - z;
        final double h = y - x;
        final double l = a / h;
        final double k = 1 + (y - (int) Math.pow(x, kvadrat));
        final double m = l / k;
        final double n = f * m;
        System.out.println("fi= " +n);
    }
}