I recently wrote a simple recursive program that chooses K objects out of N (I was asked to use the variables N choose the R, however) total objects. Here is the code:
int n = 0;
int r = 0;
//the total number of objects defaults to 0
String nChoice = JOptionPane.showInputDialog(null, "How many objects are there to choose from?");
String rChoice = JOptionPane.showInputDialog(null, "How many object are to be chosen from this group?");
try {
n = Integer.parseInt(nChoice);
[Code] ....
It works fine, however in my class we were given two different formula to implement into our code. I used the one above, obviously. However, the second formula we were given was:
C(n,R) = n!
-------(R!(n-R)!)
I had to get the spacing right.
How do I read this formula? How could it be implemented? What are the benefits (if there are any) from using one method over the other? Which method of calculating N choose K (or, in my case, N choose R) would be more widely accepted?
I have a requirement where I have a class as Page which itself contains ArrayList<Page>.Here ArrayList<Page> is nothing but the pages which are accessible from the base Page.I know the depth level ( reading from file) which means how many level I need to go to identify more pages.BUT the problem is how to set the base Page class. I need to set the base Page class but for that I need the objects for the subsequent pages and hence an iterative type of implementation.
SO for my project, we have to create a program where we input two four letter words, and using a list of words our teacher provided us and only changing one letter at a time, make the words match.For example, you input BALD and CALL and it would output BALD BALL CALLWe have to use recursion to do this, and I'm totally lost as to where to even begin.
I have small project to be implemented in Java, which, expected the management of a parking.
The project has a class abstract Vehicle, whence derive three classes: Car, Motorcycle, Heavy Vehicles; the cost estimated time for the 3 types of vehicles are: 2€ for Cars, 1€ for Motorcycle and 5€ for H.V.
In addition, in class Ticket will be stored the arrival time of the customer and the characteristics of his vehicle.
Finally, in the class Parking(which provides 80 places available), here it should be added the various types of vehicles.
Now, I though of using an Collection, as Set.. So that they can not, two Vheicle with same license plate.
I need to choose the value of a list item in jsp. There are many employees in various departments and i need to choose that employees in department wise.
Example. I have two list items in jsp
1. Select dept_no,dept_name from departments 2. SElect emp_name from employees, departments where emp_dept_no=curr_dept_no and curr_dept_no = dept_no
These two are the list items. When i choose the department from the first list item i need to display the employees in that particular department in the second list.
I have good knowledge of servlet,jsp. I've also worked on mvc pattern and now looking to learn a web framework but i'm not sure which to choose between spring mvc OR struts.Should i first do struts and then go for spring or can i choose spring directly?
I am using eclipse for this project. Every time I run this program the choose method will always choose 0. Ignore the Sleep.sleep() method, there is another class in the program that performs it.
import java.util.Scanner; public class gamestart { public static int num; public static String name; public static String diff; public static String choice;
How to remove multiple objects that are onscreen in a java graphics program(specifically the one from the acm library). The clearAll works fine but I would like to keep the background in my frame. I just want to be able to do something like removing all the trees by typing in a phase into a console program. Here is a small snippet of code with details of what I am trying to achieve.
Java Code:
public void command(){ Dictionary dic=new Dictionary(); //dic list of all phases that will either make animations or remove things in a graphical window String line = readLine("Type here: "); if (line.equals(dic.clearActions[i])) { cleared=true;
When I run my program and choose option 2 to get contact details I am expecting it to display as follows (First Name, Last Name): Contacts how have been entered:
0) John Doe 1) George Smith 2) Nancy Davis
Please enter the number corresponding to the contact you would like to view:
Instead for a personal contact it is displaying as follows:Contacts who have been entered:
0) Doe 1 F St. (last name, address)
Please enter the number corresponding to the contact you would like to view:
Instead for a business contact it is displaying as follows:Contacts who have been entered:
0) 1 F St. jd@gmail.com (address, email)
Please enter the number corresponding to the contact you would like to view:
Then when I enter the number to display the contact for personal it is returning me only first name and business is only returning me first and last name. It should be returning the full contact info that was put in during the add contact step. I thought I programmed everything properly but it isn't displaying what I want to seeMy code is listed below.
ContactList
/* * To change this license header, choose License Headers in Project Properties. * To change this template file, choose Tools | Templates * and open the template in the editor. */ package contactlist; import java.util.ArrayList; import java.util.Scanner;
I will try to explain what i want to code , a HiLo game where the user can choose up to 3 different levels(1-10, 1-100, 1-1000) with these 3 methods
public static void main(String[] args) {...} public static int playGame(int maxNumber) {...} public static void giveResponse(int answer, int guess) {...}
with no Random , i will use the:
int number = (int)(Math.random() * max) +1; to generate numbers
I have tried so many times , but i don't get it ....
My code so far :
import java.util.Scanner; public class HL{ public static void main(String[] args ){ Scanner s = new Scanner(System.in);
I am trying to create a slightly modified cash register. The user will enter the amount of the item, the payment received, calculate the change/refund, and then allow the user to choose the preferred bills.
import java.util.Scanner; public class Register { private static Scanner input; public static void main(String[] args) { input = new Scanner(System.in); System.out.println("*****CASH REGISTER*****" ); System.out.print("Item Amount: " ); int amount = input.nextInt();
[Code] ....
I will try to clarify the code, to make things a little easier to interpret. in the refund method, I have set up a 2-d array to exist and function as an excel sheet. The refund amount is passed to the method and compared to each bill of the array. Once the refund is determined to be greater than a bill, the user is prompted to enter the preferred bill type. This is where my problem is...I would like the program to then calculate the number of bills and keep a tally of those bills in the 2nd column and then determine the new refund amount at which point the user will be prompted again to determine the desired bill.
Then print out the array of bills that are not equal to 0.
I'm writing a graphical program with several Label objects. One of them is supposed to constantly change color. I tried to do it with while loop like this:
while (true) {label1.setColor(Color.blue); pause (80); label1.setColor(Color.red); pause (80);}
However, the rest of the code (after the loop) is never reached because the loop never ends. Is it possible to use infinite loop like this? And, is there any other way to handle permanent processes that are supposed to run as long as the program is running (like, in this case, blinking Label)?
I'm making a program that displays information for "employee" objects of different types. This works with a hierarchy that goes Person→ Employee→ Fulltime/Adjunct, and a driver that tests the inheritance. The Person class is given and only supplies the name, the employee class manages the year hired and the ID, and the types of employee classes manage the salaries.
One object (called staff[2]) is supposed to first be printed with default information and then later updated via set methods. I figured out how to update the name, but I don't know how to update the rest of the information because the employee's name is managed in the Person class and the reset of the information is managed in the less-general classes, and the objects are all in an array of Person.
How do I call the set methods necessary to update more of staff[2]?Output (scroll to see the updating section)
The current year is 2012
Name: Flintstone, Fred ID Num: BR-1 Year Hired: 2005 Years Of Service: 7 Salary: 65000.12 Fulltime Type Employee
I'm trying to implement a non-recursive version of the insertion method, but I'm having a bit of trouble. From what I can tell, it's only returning the last two node..
public void insert(Key key, Value val) { root = insert(key, val, root); } private Node insert(Key key, Value val, Node x) { if(x == null) { x = new Node(key, val, 1);
As one of the methods of my IntTree tree I have to implement a method that multiplies the level number with the sum of the nodes on the current level. So far I have this, and it doesn't work. What I am wondering is am I on the right track at all with the second return statement?
public int depthSum(){ return depthSum(overallRoot); } private int depthSum(IntTreeNode root) { if(root==null) return 0; int level = 0;
I am not sure how to add all the possibilities of elements in an array and find the greatest sum. I want to do this recursively. I don't need any code. How I would do it.
I was told to write a method that adds up the sequence of the formula (n/2n+1) eg. 1/3 + 2/5 + 3/7 etc. simple enough i suppose. my method is below
public static double Series(int n){ if (n==0)return 0; else return (n/(n*2+1)) + Series(n - 1); }
However for some reason or another it returns 0 for any number that is put in. I've written it dozens of different ways with no change and i feel like something fairly obvious is being missed on my part. I am honestly intrigued and interested as to why this is happening. i assume it has something to do with the way i put the actual formula in cause if i put anything else in like simply n the recursion would work as expected.
I'm trying to understand the concept behind this recursive method called rangeSum. This method sums a range of array elements with recursion. I tried summing the elements of 2 through 5, and I tried writing down what actually happens when java executes the program, but what I get when I try to figure it out by paper is different from what netbeans gives me. Here is a snapshot of my scratch work as well as my source code. Netbeans gives me "The sum of elements 2 through 5 is 18" when I try running it but it I get 12 when I do the recursion on paper. I know that the source code is correct because it's out of the book but what am I doing wrong when I try figuring it out by hand?
XML Code:
package recursivecall; import java.util.Scanner; /** * Author: <<Conrado Sanchez>> Date: Task: */ public class RecursiveCall {
I wrote this tail recursive function that mirrors the iterative version, except that the loop in the iterative version is replaced by an if statement here and then a recursive call. Is this truly recursive? I have seen the fibo(n-1) + fibo(n - 2) version, but is this also an acceptable recursive solution? Why is it never solved this way?
public class FiboRecursive { public static int fibo (int n) { int sum = 0; int n1 = 1; int n2 = 1; if (n == 1 || n == 2) { sum = 1;
