Challange-Response Authentication

import java.io.*;
import java.util.Random;

/**

 *

 * @author Sanket

 */

public class Main {
    public static void main(String[] args) throws IOException {

        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        String originaluser = "sanket";

        f:
        for (int j = 0; j < 3; j++) {
            System.out.print("Eneter User Name : ");
            String username = br.readLine();

            if (originaluser.equals(username)) {
                System.out.println("Valid user name");
                Random rgenerator = new Random();
                int x = rgenerator.nextInt(100);
                int y = x * 10;

                System.out.println("Challenging number is : " + x);
                System.out.print("Enter Password : ");
                int pass = Integer.parseInt(br.readLine());

                f1:
                for (int z = 0; z < 3; z++) {
                    if (z == 1 || z == 2) {
                        System.out.println("Retype password : ");
                        pass = Integer.parseInt(br.readLine());
                    }
                    if (pass == y) {
                        System.out.println("valid user");
                        break f;
                    } else {
                        System.out.println("invalid password");
                        if (z == 2) {
                            System.out.println("access denied");
                            break f;
                        }
                    }
                }
            } else {
                System.out.println("Invalid user name");
                if (j == 2) {
                    System.out.println("access denied");
                }
            }
        }
    }
}