Write the following method that shuffles an array list of numbers.
public static void shuffle(ArrayList<Number> list)
package shuffleArrayList;
import java.util.ArrayList;
import java.util.Arrays;
public class ShuffleArrayList
{
public static void main(String[] args)
[code]....
I had to write a program that prompts the cashier to enter all prices and names, adds them to two arrays lists, calls the method that I implemented, and displays the result and use 0 as the sentinel value. I am having difficulty coming up with a for loop in the method, I believe I have the condition right but I am having trouble with the statements. I now know that String does not have the get property, but I have only done examples with integers and I am not very good with for loops and wouldn't know how to fix it.
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
ArrayList<Double> sales = new ArrayList<Double>();
ArrayList<String> names = new ArrayList<String>();
System.out.print("Enter Number of Customers");
double salesAmount;
System.out.print("Enter Sales for First Customers");
salesAmount = in.nextDouble();
while(salesAmount != 0)
[code]....
How to convert numbers into string without using an array and a method ....
Example of arrayed code:
The code here is working but i want to use the other way for not using array just like switches and if and loops only.
I made a code here but i did'nt run what i want to output .....
package UnderPackage;
import java.util.Scanner;
public class NumberToWords {
static Scanner input = new Scanner(System.in);
public static void main(String[] args) {
int number;
int b;
[Code] ....
So I have created a array list of pizza toppings, only 4 in total, and each ingredient needs to have a cost property. I'm supposed to access the cost through a get / set method, as the user can create their own pizza and it will total up the cost, but how to.
View Replies View RelatedI'm making a method to take an array of integers and rearrange the numbers from least to greatest, using for loops.
I'm getting the error "java. lang. ArrayIndexOutOfBoundsException: 8,
Portion of the ArrayMethods class with the sorting method
Java Code:
public static Integer[] sortArray (Integer[] a)
{
int swap;
for (int i = 0; i < a.length; i++)
[code]....
I'm trying to make a program that generates 20 random integers between 1 and 20 and then prints the list of random numbers to the screen. After that, I want to print a different list to screen with the same numbers from the first list only skipping any number that has been already printed to the screen. So two lists are printed to the screen. The first one has 20 random numbers. The second one has those same 20 numbers but only prints the numbers in the first list that aren't duplicated. So if m
y list of 20 random integers contains three 2s and two 14s, only one 14 and one 2 is printed to the second list. Currently, my code generates 20 numbers from 1 to 20 and stores those numbers in an array but I don't know how to print solve the second part of my problem. I don't know how to print the s different list only without duplicate numbers. As a result, my output is nothing because it doesn't print any number from the first list as oppose to skipping only duplicate one.
public void randomNum(){
System.out.println("Twenty random integers: ");
int max = 20; // max value for range
int min = 1; // min value for range
Random rand = new Random();
int[] all = new int[20];
[Code] ....
I am having a little trouble with a part of my Java assignment that needs to have linked lists in it.
I need to write a public method that takes an array of type object to load strings into a linked list.
Program is to list all prime numbers between two entered numbers.
import java.util.Scanner;
public class question6 {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
System.out.println("Enter lower int:");
int x = input.nextInt();
[Code] .....
I've just written a program that generates 100 numbers that range from 0 ~ 25 using arrays, the program calls another method that sorts the even numbers into a separate array and returns the array. I need it to display both arrays, however, when I run my program, the numbers of both arrays are mixed together, and I'm not sure how to separate them.
[ public class Array1
{
public static void main(String[] args)
{
int array [ ] = new int[100];
for (int i = 0; i < array.length; i++)
{
array[i] = (int) (Math.random() * 26);
[Code] .....
Write a program to maintain a list of the high scores obtained in a game. The program should first ask the user how many scores they want to maintain and then repeatedly accept new scores from the user and should add the score to the list of high scores (in the appropriate position) if it is higher than any of the existing high scores. You must include the following functions:
-initialiseHighScores () which sets all high scores to zero.
-printHighScores() which prints the high scores in the format: “The high scores are 345, 300, 234”, for all exisiting high scores in the list (remember that sometimes it won’t be full).
-higherThan() which takes the high scores and a new score and returns whether the passed score is higher than any of those in the high score list.
-insertScore() which takes the current high score list and a new score and updates it by inserting the new score at the appropriate position in the list
I have a GUI with a textArea for the user to input numbers, a button which should "listen" for those numbers, and then a textField to display the sum. I have my code working for user input of one number; but I'm at a loss as to what sort of loop I need to create to get it to read each line of input. I wasn't sure whether to put this in the beginner forum or here, because I am definitely a beginner.
So my code thus far that works with one input:
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JOptionPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;
[Code] ....
Java Code:
class MyLinkedListH1
{
private class Node
{
private Node link;
private int x;
}
private Node first = null;
public void addFirst(int d)
{
Node newNode = new Node();
[code]...
why this isn't displaying the last digits of the linked it actually isnt displaying any numbers in side the linked list.
I am trying to create doubly linked list that can hold huge numbers (i.e. 123456789) and add them together. I have seen some examples on how to do this for linked list, but none really for doubly linked list.
Here is my test driver:
public class HugeNumberDriver
{
/**
* Main method with some test code
*/
public static void main(String[] args)
{
// Create a HugeNumber that is 123456789
HugeNumber h1 = new HugeNumber();
for (int i=9; i>=1; i--)
[Code] ....
Output:
h1 is 987654321
h2 is 88888888885555555555
Exception in thread "main" java.lang.NullPointerException
at HugeNumber.<init>(HugeNumber.java:52)
at HugeNumberDriver.main(HugeNumberDriver.java:29)
As you can see the numbers are displayed incorrectly and the rest of the program does not run. I have a feeling that it has to do with my deep copy constructor or my addDigit() method
the prime numbers from 1 to 2500 can be obtained as follows. From a list of the numbers of 1 to 2500,cross out al multiples of 2 (but not 2 itself). Then, find the next number (n, say) that is not crossed out and cross out all multiples of n (but not including n).
Repeat this last step provided that n has not exceeded 50 (the square root of 2500). The numbers remaining in the list (except 1) are prime. Write a program which uses this method to print all primes from 1 to 2500. Store your output in a file called primes.out.
Right, so I got this method that creates and sorts 2 lists. What I want to do is merge these lists into a third list, have it sorted, and then print the contents of the list. The problem is, I'm tired and I don't remember how I can print it.
import java.util.*;
public class MergeTwoSortedListWilson {
public void CHANGEME() {
// To do
ArrayList<String> aList = new ArrayList<String>();
aList.add("Banana");
[Code] ...
MergeTwoSortedListWilson.java:35: error: cannot find symbol
System.out.println(aList);
^
symbol: variable aList
location: class MergeTwoSortedListWilson
1 error
I'm trying to do a program where I add numbers using the pencil method (i.e. add 9 + 5 and get 14, carry the 1, drop down the 4).
import java.io.*;
import java.util.Scanner;
public class add_arrays
{
public static void main(String[] args)
{
Scanner input = new Scanner(System.in);
String s1, s2;
[code]...
Is there a particular implementation of a linked list you are referring to in your question?
View Replies View RelatedI'd like to know how to return a new array, I wrote in a method below the main method. I want to print the array but system.out.print doesn't work for arrays apparently. What structure i should use?
View Replies View RelatedImplementing the add(int i, E o) method for a SinglyLinked List.
public void add(int i, E o)
// pre: 0<=i<= size()
// post: adds ith entry of list to o
I'm still working with the singlylinkedlist data structure and trying to return a string of individual characters stored in each node. ( head--('J')---('A')---('V')---('A')---tail ) Hopefully this beautifully executed depiction to the left will clarify.
This is what I came up with after designing the algorithm w/ pen and paper. I know that I'm not accounting for the OutOfBound errors, an empty list, or an index < 0.... I will get to that.
Right now, I'm not sure why my assignment to the character array, ' chars[i] = cursor.getLink(getElement()); ' , is not working. The two methods getLink and getElement, type Node and T, respectively, exist in my Node class which is a private nested class in MySLList. Why would I be getting the following error: "The method getElement() is undefined for the type StringX" ? Is this a good design and implementation of the substring method?
public String substring(int index) {
char[] chars = new char[(getSize() - index)]; //getSize() defines the size of list in MySLList
Node cursor = null;
//Set the cursor to the node = index
if(cursor == head) {
[Code] ....
So I have to write all the methods for a LinkedListQueue. I've got isEmpty, enqueue and dequeue working correctly (I think) but I'm having trouble with the toString method. I tried to do it recursively and it works if there is only one element in the list, but with multiple elements it throws a StackOverflowerror exception. I've tried it multiple different ways, but I can't seem to figure out how to print it out with out clearing everything. We haven't been taught StringBuilder or .append yet, which I saw a lot of as I was looking for solutions, so I can't use those.
public class LinkedQueue<T>
{
protected LLNode<T> front; // reference to the front of this queue
protected LLNode<T> rear; // reference to the rear of this queue
private T info;
public LinkedQueue()
{
front = null;
rear = null;
[Code] ....
and this is the ITD used with it, for some reason it has the "empty the queue" function as a choice but we weren't assigned that function, so just ignore it.
import java.util.Scanner;
public class ITDLinkedQueue
{
public static void displayMenu()
{
System.out.println("(1) display menu");
System.out.println("(2) check isEmpty");
System.out.println("(3) enqueue");
System.out.println("(4) dequeue");
[Code] ....
I am trying to create a method that reverses the digits of a number.
import java.util.*;
public class KDowlingWeek7 {
static Scanner console = new Scanner (System.in);
//Scanner input = new Scanner(System.in);
public static void main(String[] args) {
[Code] .....
The error I get is :
Error: cannot find symbol System.out.print(reverseDigit + " ");
Symbol: variable reverseDigit
Location: class KDowlingWeek7
I am trying to put a reference to a given subclass object into a linked list, and then come back later, and invoke a method of the subclass object that is in a given spot in the linked list. This produces an error because Object does not have that method. Is it necessary to cast the object to the correct subclass every time I want to use one of its methods, or is there a way to convince the JVM to treat it as always of type MySubclass?
View Replies View RelatedI'm trying to write an indexOf() method that will return every time a value occurs in a linked list. I need to use my user-created linked list not the built in Java linked list. For example in a linked list of characters: "i, p, z, z, n, d, p, z" when I search for "z" it should return position variables for 3, 4, and 8. Currently what I have is obviously only returning the first instance.how I can return more than one instance?
public int indexOf(char input) {
LLNode currentNode = this.first;
int position =1;
boolean found = false;
[code]...
So I need to generate 10 random integers in the range 1-20 but i have to store them in an array called numbers. Then I have to call a method called displayArray which displays the contents of the array and for the assignment i have to use a for loop to traverse the array. The method header for the displayArray method is:
public static void displayArray(int[] array)
This is what I have done
public class RandomIntegers {
static int numbers = 0;
public static void displayArray(int[] array) {
System.out.println(numbers + "Numbers Generated");
[Code] .....
Write a method that returns a new array by eliminating the duplicate values in the array using the following method header: public static int[] eliminateDuplicates(int[] list). The thing is that I found the working solution that is written below, but how it works. How to eliminateDuplicates method done with flag and flag2.
Here is the code:
Java Code:
import java.util.Scanner;
public class Exercise06_15 {
public static void main(String[] args) {
java.util.Scanner input = new java.util.Scanner(System.in);
int[] numbers = new int[10];
System.out.println("Enter ten numbers: ");
[code]....