When you "system.out.print(arraylist)" an arraylist, it will give you something like [item1, item2].
Im wondering how I can remove the "[" and "]" brackets fromt he printout, or even if i pass it in as another variable.
I am stuck on this exercise and I don't know what exactly is wrong. I think it's something with the .remove and the for each loop, but I am not sure.
public class seven {
public static void main(String[] args) {
ArrayList<String> list = new ArrayList<String>();
list.add("aaa");
list.add("brr");
list.add("unni");
[Code] ....
This is what i get
Exception in thread "main" java.util.ConcurrentModificationException
at java.util.ArrayList$Itr.checkForComodification(Unknown Source)
at java.util.ArrayList$Itr.next(Unknown Source)
at seven.removeDuplicates(seven.java:24)
at seven.main(seven.java:18)
I am working on a java program that is called OrderedVector which is basically a storage or list that grows and shrinks depending on the amount of data is put in. Most of the methods in my code are correct and working, the only real issue I have lies with either the remove(E obj) method or remove(int index) method. This is the driver I am currently using to test my remove method,
public class Tester {
public static void main(String[] args) {
OrderedListADT<Integer> v;
v = new OrderedVector<Integer>();
for(int i = 0 ; i <= 9; i++){
v.insert(i);
[code]....
the output I am receiving is
Removing 0
Size of data structure is 9
Removing 1
Size of data structure is 8
Removing 2
Size of data structure is 7
[code]....
As you can see, when I am calling the second for loop, none of the elements are being removed by my methods but the first for loop is working just fine.
Here is my code for the OrderedVector
package data_structures;
import java.util.Iterator;
import java.util.NoSuchElementException;
public class OrderedVector<E> implements OrderedListADT<E>{
private int currentSize, maxSize;
private E[] storage;
public OrderedVector(){
currentSize = 0;
[code]....
So overall, my remove method should implement binary search and remove elements using either an index or the object value type.
Im not sure why the nodes are not being deleted. Is a part of my logic wrong?
public void delete(String s) {
Node temp = find(s);
if (temp==null) {
return;
}
Node prevTemp = temp.prev;
Node nextTemp = temp.next;
[Code] .....
public class werek4d {
public static void main(String[] args) {
int counter = 1;
int[] anArray = new int[101] ;
for (int i = 0; i <= 99; i++){
anArray[i] = i + 1;
System.out.println(i + ": " + anArray[i] + " ");
[Code] ....
My aim is to generate a lists containing 1 to 100. I will then count the number of integers divisible by 3. After doing so, I want to delete the integers that are NOT divisible by 3 in the lists. I tried doing it, but I seem to keep on getting the same lists.
I was trying remove duplicates element from my array without using collection API but i didn't got any output from my code.Although it is compiled successfully but on execution it didn't give any output. I guess there must be some problem in function Duplicate
Java Code:
class Union {
public static void main(String...s) {
Union M=new Union();
int x[]=new int[]{1,0,1,4,10,10,10,3,567,4,3,33};
int y[]=new int[]{5,4,5,4,5,4,2,3,3,1,0};
int []w=M.merge(x,y);
[Code] .....
Ask the user to enter a sequence of at most 20 nonnegative integers. Your program should have a loop that reads the integers into an array and stops when a negative is entered (the negative number should not be stored). Invoke the average method to find the average of the integers in the array (send the array as the parameter).
how can I remove the negative number from the array and calculate the average of the posive elements without the negative ones? This is my code so far...
import java.util.Scanner;
import javax.swing.JApplet;
public class Parameters
{
//-------------------------------------
//Calls the average and minimum methods
//with different numbers of parameters
[code]....
I need to call the method to remove duplicates form my array, but it won't let me call the method, or I'm doing it incorrectly which is probably it.
import java.util.*;
public class C_6_15_EliminateDuplicates {
public static void main(String[] args) {
int[] numbers = new int[10];
Scanner input = new Scanner(System.in);
System.out.println("Enter " + numbers.length + " numbers: ");
for (int i = 0; i < numbers.length; i++)
[Code] ......
I have just started working with linked lists. I have a linked list of Objects and I want to be able to search for a specific object. But currently my code continues to return false. Also how would I go about removing the first index of the linked list.
public static void main(String[] args) {
LinkedList<Cookies> ml = new LinkedList<>();
int choice = 0;
while (choice >= 0) {
choice = menu();
[Code] ....
Question 1: I am working on an assignment where I have to remove an item from a String array (see code below). When I try to remove an item after entering it I get the following error "java.lang.NullPointerException." I am not sure how to correct this error.
Question 2: In addition, I am having trouble figuring out how to count the number of occurrences of each string in the array and print the counts. I've been looking at other posts but they are more advanced and I have not yet learned how to use some of the tools they are referring to.
private void removeFlower(String flowerPack[]) {
// TODO: Remove a flower that is specified by the user
Scanner input=new Scanner(System.in);
System.out.println();
System.out.println("Please enter the name of the flower you would like to remove:
[Code] ....
For our final project we're making a game. I'm "trying" to do battleship in 2D, but its not going well. at all. I've started it but how to get the arrays which are my rows in the game to printout, and i need to put them into a seperate method and all them.
Scanner input = new Scanner(System.in);
String userN;
String B1;
String H1;
H1 = "onethree";
[code]....
I am designing simple app which would store data about users and generate standard letter and print sun ray card for this user. I know how to build UI, how to validate it etc. I know how to store data in database, but I don't know how to deal printing.
I have MS doc template documents they contain jpg pictures, and unusual formatting Is there a way of actually pulling those templates and do the merge and perform print operation? If it is not easily done, what else I could do? I would need to have option to easily edit those templates in case of any changes.
I am working on a program to evaluate an expression without brackets using stacks. I am getting the following error :
3+1*2+4
-2.0
Exception in thread "main" java.util.EmptyStackException
at java.util.Stack.peek(Stack.java:102)
at java.util.Stack.pop(Stack.java:84)
at assignment2.Evaluate.main(Evaluate.java:42)
I imported the Stack from java.util.Stack
package assignment2;
import java.util.Scanner;
import java.util.Stack;
public class Evaluate {
public static void main(String[] args) {
Stack<String> ops = new Stack<String>();
[Code] ....
What is causing this error? Does it look like the program should function as intended?
At this moment in time my program compiles and runs as I want it to, but when I look at my code I see that my While Loops braces are placed inside my Try Block. When I move these braces outside of the Try Block, next to the WhileLoop, the program doesn't run like I want it to.
Likewise, when I place the While(answerIsCorrect) inside the Try Block, it doesn't work like I want it to either.
Also, my problem is on Lines 17 and 18.
import javax.swing.*;
import java.util.Random;
public class SwingInputExample
{
public static void main(String args[])
{
int firstNumber=0;
int secondNumber=0;
int correctAnswer=0;
String studentGuess = null;
[Code] ....
I'm trying to get my output to be displayed without the brackets.The output looks like this
22 ([1, 2, 11])
33 ([1, 3, 11])
44 ([1, 2, 4, 11, 22])
55 ([1, 5, 11])
66 ([1, 2, 3, 6, 11, 22, 33])
77 ([1, 7, 11])
But I want it to have no brackets displayed so it looks like this
22 (1, 2, 11)
33 (1, 3, 11)
44 (1, 2, 4, 11, 22)
55 (1, 5, 11)
66 (1, 2, 3, 6, 11, 22, 33)
77 (1, 7, 11)
import java.util.ArrayList;
public class Palindrome {
public static void main(String[] args) {
int e = 0;
// palindromic composite number
int drome = 0;
[Code] ....
I have spent the past 12 hours on it and have gotten no where. I need to create a program that will calculate different tax brackets. I have tried all combinations I can think of and can't get it to work!!! I am literally about to go insane! I need the program to calculate tax will be 1% for anything up to $50000. If the tax is over $50000, you keep that 1% of $50000 and then add the remaining. So for an income in the second range, it would be 1% of $50000, and then 2% of (income - $50000). This then continues for each range.
The problem I'm having is getting it to display the correct interest rates. I am not asking for you to write it for me. I want to learn. But at this point I have exhausted all resources available to me.
import java.util.Scanner;
public class Project3taxinfo {
public static void main(String[] args) {
final double RATE1 = 0.01; //1% tax on the first $50,000
final double RATE2 = 0.02; //2% tax on the amount over $50,000 up to $75,000
final double RATE3 = 0.03; //3% tax on the amount over $75,000 up to $100,000
final double RATE4 = 0.04; //4% tax on the amount over $100,000 up to $250,000
final double RATE5 = 0.05; //5% tax on the amount over $250,000 up to $500,000
final double RATE6 = 0.06; //6% tax on the amount over $500,000
[code]....
I'm using this try statement to check for errors in input in my Tic Tac Toe game. The problem I have having is I don't understand why this error is happening. It's preventing my code from compiling. I've tried inserting an else statement and multiple brackets at various places with no success.
Java Code:
public void play(){
Scanner input = new Scanner(System.in);
int row, col;
char currPlayer = 'X';
[code]....
Im trying to do this program but I keep getting Empty Stack Exception when I execute balancedBrackets. I know that push and pop methods works, but I'm not so sure if my logic for balancedBrackets is correct.
public void push(T t){
if(this.top+1==this.size){
duplicateCapacity();
}
else{
top++;
arr[top]=t;
[Code] .....
How do you format an arraylist?
Mine looks like this:
[<?xml version="1.0" encoding="UTF-8" standalone="no"?> <DefEnv id="Dev">, <Envt id="Test">, , <DB id="DM">,
But I want it to look like: I'd prefer if the '[' , '<>' and ',' were not on them also but I'm not too bothered about that bit.
[<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<DefEnv id="Dev">,
<Envt id="Test">, ,
<DB id="DM">, ]
I am creating a hangman game and I want to read in a list of words from a text file, but after the user inputs the name of the text file. I get 'Exception in thread "main" java.lang.NullPointerException'.
Here is the code, where I think the problems lie.
public void runModel(){
ArrayList<String> pirateWordsList = new ArrayList<String>();
System.out.println("What is the name of the file you would like to load? (The file included is called piratewords.txt'");
Scanner in=new Scanner(System.in);
String file=in.next();
load(file);
[Code] ....
The full error message is this:
Exception in thread "main" java.lang.NullPointerException
at uk.ac.aber.dcs.pirate_hangman.Model.load(Model.jav a:108)
at uk.ac.aber.dcs.pirate_hangman.Model.runModel(Model .java:45)
at uk.ac.aber.dcs.pirate_hangman.Main.main(Main.java: 6)
I have 3 classes Pet, Cat and Dog classes. Cat and Dog classes are childs of Pet class.
Each pet has the properties of
private String myName;
private int myX;
private int myY;
private int mySpeed;
private int myAge;
I have an array list which creates 100 dogs. How can I print out the dogs with the two highest age values?
Im trying to create a program in which I read line by line the contents of a text file, and then report each letter along with its frequency. I was wondering how to read through the lines and process it so that my program knows to increase by a number each time a letter appears in my text file. For example, if A appears in my file 5 times, B 3 times, and C 0 times I want to eventually print out
A -- 5
B-- 3
C-- 0
My first thought was to do this using array lists but is there any way I could do this without using one?
method called []getLetterGrades but the only hint My professor told me was that I needed to declare another array list for this method and he wouldnt tell me anything else so bummer. But I don't understand why if what we are returning is a char. It would make sense to return an array list of char to get letter grade. Which is what i did but since the function is a char, the array list character wont work as a return.Primarily i would like to know the type that is needed. I just want an explanation for an array list in this method and how it would serve in this method.
import java.io.File;
import java.util.ArrayList;
import java.util.InputMismatchException;
import java.util.Scanner;
[code]....
Directions: public static void initialize(ArrayList names, ArrayList sores)
You should write a function that sorts both array lists, based on the values in the scores array list. This is one of the more conceptually challenging parts of the assignment. You want to sort the scores array list, and simultaneously alter the names array list so that the names continue to line up with their respective scores by index. In the example data above, when the score 9900 moves to the first element of the scores array list, the name "Kim" should also be moved to the top of the names array list. The function should have the following signature:
I'm having trouble figuring out how to sort the lists.
import java.util.ArrayList;
import java.util.Scanner;
public class Assignment5
{
/**
*/
public static void main(String[]args) {
intializeArrays();
[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]....
Here I have an enum class
public enum Money{
ONE_PENNY(1),
TWO_PENCE(2),
FIVE_PENCE(5),
TEN_PENCE(10),
TWENTY_PENCE(20),
FIFTY_PENCE(50),
ONE_POUND(100),
TWO_POUNDS(200);
private int coin;
Money(int c) {
coin = c;
}
int showCoin() {
return coin;
}
and for a test class, I need an array list with a couple of coins in it (i.e. ONE_POUND, TWO_POUNDS) and a loop that adds together the values of the coins in the list and prints the result. How can I do this?