public void myFunc(MyNode n, ArrayList<MyNode> path) {
boolean hasChildren = false;
path.add(n);
int index = path.indexOf(n);
ArrayList<MyNode> statefulPath = new ArrayList<MyNode>();
[Code] ....
I have similar code that I stepped through in a debugger. After running the code I found that it built the desired tree, in this case a root node H with left child L and right child P. I want list of lists to contain all paths from root to leaf. I expected [H, L] and [H, P]. I discovered that statefulPath is not stateful; after a recursive stack frame pops, statefulPath still contains n! But that stack frame just popped! I expected to see statefulPath be [H] in the debugger and it was [H, L]! So I later have a list [H,L,P] which I don't want. How do I make the statefulPath list I want for my algorithm?
Why do I make private Node<AnyType> next;And why do I have an inner class of Node for a linked list?I had the same topic in C, but there it was somehow easier than in java. Because there you have pointers.
Write a Java function Sum2List that takes two lists L1 and L2 of the same size and returns list L that contains the sum of data inside the corresponding nodes of lists L1 and L2.
ex: L1 = {1,2,3} L2 = {4,5,6} L = {5,7,9}
I do not know how to iterate through two different lists >>
I have used unmarshalling concept to retrieve the data elements... I have to check whether the elements satisfy few regulations when compared with data in Database. So, i thought of grouping the employees depending on EType. I have created a Map with linkedlist of employees. Say Map<String, LinkedList<Employe>>EmpMap=new Map<String, LinkedList<Employe>>();
I have already created a class named Employee which has all the setter and getter methods for employee.
Here am going to take Etype(Employee type) as key and linkedlist(list of employees of certain type) as value. How to iterate these linked lists and place them in my Map.
What is going on here in the main class is a zoo that requires information to be read from and saved to a .txt file. I have made three arrayLists for each .txt file, I am getting errors for illegal start to an expression
import java.io.*; import java.util.*; public class ColumbusZoo { public static void addHelper(ArrayList<DomesticAnimal> a){ Scanner s = new Scanner(System.in); System.out.println("What species");
I am trying to make a game, for some reason i have begun to get a java.lang.StackOverflowError.
I am not exactly sure how i can fix it. only removing line 14 from infopannel1 (and everything that used that class.) seems to work. im not sure what else i can do to fix it. or why its resulting in stack overflow for that matter.
I am putting in a link for the files i wrote this using bluej (several classes have no relevance, errorv2, demonstration, folderreadertest, ReadWithScanner, saveloadtest, menutest,rannum, and menutestTester. are all irrelivent to my problem.)
How to add the sum of an array with a recursion, but I don't understand how to use recursion. I just understand that it calls back the method. I am nearly done with the code.
import java.util.Scanner; class Question1{ public static void main(String[]args){ Scanner s = new Scanner(System.in); int size, sum; System.out.println("Please input how many numbers will be used"); size=s.nextInt();
I am working on a assignment that has to do with array lists, it mainly has to do with adding new elements, telling then where it is it located, if the memory block is empty , ect. so far i have been having problems with my indexOf method which should display the array cell number that a input element E is in, and if it is not in there it should display a -1.
public class MyArrayList<E> { private E[] data_store = (E[])new Object[2]; private int sizeofa = 0; private void resize()// makes the array list bigger if need { E[] bigspacemaker = (E[])new Object[data_store.length * 2]; for(int x = 0 ; x< sizeofa ; x++)
[Code] ....
Error message: Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 512 at MyArrayList.indexOf(MyArrayList.java:28) at MyArrayListDemo1.main(MyArrayListDemo1.java:26)
I am familiar with Java but new to JSP. I have a Java Servlet app where user actions are recorded in a SQL Server database amd I now need to quickly put together a JSP front end application to view user actions. I want two drop down boxes to filter the results that will be displayed in a list box. What I need is the first drop down list box to show unique user names that have logged in. I can interrogate the database with the following SQL;
"SELECT DISTINCT(USER_ID) FROM AUDIT_MESSAGE"
Then when a user is selected from the first drop down list box (perhaps some sort of on change event) a second drop down list box shows the logins times of the selected user. Again I can interrogate the database with the following SQL;
SELECT SESSION_ID, EventTIME FROM dbo.AUDIT_MESSAGE WHERE OPERATION = 'loginResponse' AND RESULTS = 'OK' AND USER_ID = 'firstdropdownlistselection'
Then finally when a login time is selected in the second drop down list box all events for the selected user while logged in with that login time are displayed in the list box.
I have two JComboBox the first contains a list of patients, the second a list of antibiotics I want to make a button when I chose an antibiotic and a patient they will be added in my database (sql server)
I have a question related to the code below, that I do not understand. The aim is to count all files and subdirectories in an ArrayList full of files and subdirectories. So I have to count every file and every subdirectory.
The code concerning counting files is clear to me - every time d is of the type file I have to increment n by one. However I thought that I have to do the same thing in case d is a directory, so I would have written the same code for directories.
So what does "n += ((Directory) d).countAllFiles();" mean? In my understanding the method countAllFiles() is applied again on the object Directory ( as Directory is the class that contains this method), but how is n incremented by this? I thought n should be incremented by one as we did with files.
public int countAllFiles() { int n = 0; for(SystemFile d : content) { if(d instanceof File) { n++;
How the recursion works. I tried to figure out writing down low, mid, high at each recursive call. But I seem to be making a mistake somehow. I don't understand where the values are returned to in
I just started studying recursion and I wanted to know how to create a palindrome number going up from 1 to n then back to 1 like this: "12345...n...54321".
I've done one going downwards and then upwards like this: "n...4321234...n".
Here's my code:
Java Code: import java.util.*; public class PalindromeTest { public static void downPalindrome(int n)
The program I'm working on is supposed to read input from a file and using recursion, print the pattern of asterisks for each value until the value is either < 0 or > 25.For example, if the value was 4, the pattern would look like this
* * * * * * * * * * * * * * * *
The values are stored in a file entitled prog3.dat which looks like this
4 3 15 26 0
I've never used recursion before and haven't been able to find anything showing how it would work with this particular type of problem.Here is what I've been able to come up with so far, but I'm having problems still which I will show following the code.
import java.util.Scanner; import java.io.*; public class Program3 { public static void main(String[] args) throws Exception { int num = 0; java.io.File file = new java.io.File("../instr/prog3.dat"); Scanner fin = new Scanner(file);
[code]...
It appears to be reading the file correctly, but is only printing the top half of the pattern. Also, like I said, I'm not very familiar with recursion, so am not sure if this is actually recursion?
The program I'm working on is supposed to read input from a file and using recursion, print the pattern of asterisks for each value until the value is either < 0 or > 25. For example, if the value was 4, the pattern would look like this
* * * * * * * * * * * * * * * *
The values are stored in a file entitled prog3.dat which looks like this
4 3 15 26 0
I've never used recursion before and haven't been able to find anything showing how it would work with this particular type of problem. Here is what I've been able to come up with so far, but I'm having problems still which I will show following the code.
import java.util.Scanner; import java.io.*; public class Program3 { public static void main(String[] args) throws Exception { int num = 0; java.io.File file = new java.io.File("../instr/prog3.dat"); Scanner fin = new Scanner(file);
[Code] ....
Output:
Please enter an integer * * * * * * * * * * Please enter an integer * * * * * * Please enter an integer
As you can see, I don't know how to make it print the pattern like in the example and am honestly not even sure if this is recursion since I've never actually worked with recursion before.
I have the following code that supposed to perfrom sorting on the linked list using method sort in order usind node concept of Linked List but seems to give inlogic results. the following code tests only the values lower than the first value but i can't manage to sort the data higher than the first entered value;
/* * To change this template, choose Tools | Templates * and open the template in the editor. */
import java.util.*; public class ListNode<T extends Comparable> { ListNode<T> nextNode; T data; public ListNode(T item)
I'm working with Doubly Linked Lists and using Java Generics..
My nodes looks like this: class DNode<E> { DNode<E> previous; DNode<E> next; E element;
//and all methods inside }
My list of Nodes looks like this: class DLL<E>{ private DNode<E> head; private DNode<E> tail; private int size;
[code]....
As you can see, as arguments they get "E o"...I need to write a program, which from the main function asks the users how long is the list, and after they type it's length, I ask them to start typing the elements (integers)...and this is how my main method is written, but I can't seem to make it work, specialy when I call the "insLast" method,I guess it's because the arguments i'm giving to the function...how to read the elements and write them into the list?
public static void main(String[] args) throws IOException { DLL<Integer> lista=new DLL<Integer>(); BufferedReader stdin = new BufferedReader(new InputStreamReader(System.in)); String s = stdin.readLine(); int N = Integer.parseInt(s); s = stdin.readLine(); String[] pomniza = s.split(" "); for (int i = 0; i < N; i++) { lista.instLast(Integer.parseInt(pomniza[i])); }
I am creating a chained hash table that uses my own LinkedListclass to handle collisons. Here is where my issue is occuring: I start with an array of LinkedLists, my "hash table", intially set to null. When i wish to add a word, if the desired location is null, I create a new LinkedList, place it in that array index. I then create a new LinkedListNode and set the head of the new LinkedList to the new node.
My issue is occuring here: Whenever I set the head of my new LinkedList to my new LinkedListNode all of my previously created linkedlists also have their head changed to the new node.
My debugger shows that I am truly creating new linkedlists every time. I was afraid each array index was just pointing to a single array, but that is evidently not the issue. Below is all the relevant code
public class SetOfStrings { private int arraySize; private LinkedList[] mainArray; private int totalCount; //other methods here public boolean add(String toAdd) { int hashToAdd = hash(toAdd);
[code]....
SUMMARY: Whenever I set the head of a Linked List to a new node, it changes the head of all my linked lists to point to the same new node
where the first number is student number and the second is their grade. I need to read this information from a .txt file and dynamically create a new node containing that student's number and mark, and insert it in the correct position in the linked list (in descending order based on grade). So I get that each Node needs to contain two data types, an Int for Student # and a Double for their grade, and I'm pretty sure I've done it correctly with my StudentNode class which can be found in the source code linked above.
But what I don't get it using that class to create Nodes in my main class and then sort them based on their Double grade value WHILE they are being sorted. I just don't understand where to actually put the methods and such that does these things. Apparently I'm supposed to have three classes.
One named StudentNode which is just the node info, which I have done.
The second is called StudentList which is apparently supposed to contain the head of LinkedList and the methods I need? I'm not sure how it ties into StudentNode though.
The third and final is just the main class which I'll use to test it.
Then after all that I need to print out the median mark through a recursive method that isn't allowed to use any loops or call and functions/methods that use loops. The function should return the node in the list which contains the median mark. Secondly, in order to find the median, you need to know how many items in total are in the list. Your recursive function must calculate that number (also recursively); you may not keep track of this count elsewhere your program. Your recursive solution should only examine each node only once, and the depth of the recursion should be equal to the number of nodes in the list.
Here's my current in-progress code.
import java.io.FileNotFoundException; import java.util.Scanner; class StudentNode { private int studentNum; private double grade; private StudentNode next;
[Code] .....
I'm pretty sure the StudentNode class is fine, it's the StudentList class that I'm not sure about. I'm not sure how to add nodes since there isn't a getNext() method in the StudentList class.
I'm not sure if my understanding of PriorityQueues is correct, so I'm trying to check if my reasoning is valid. I'm supposed to compare the Big-O for arrays and linked lists for the following instructions:
Insert 100 objects having the priorities 1, 2, 3, ... , 99, 100 Big-O for Array: __________ Big-O for Linked List: ___________
Insert 100 objects having the priorities 100, 99, 98, ... , 2, 1 Big-O for Array: __________ Big-O for Linked List(Assume no tail reference): ___________
If my understanding is correct, priority queues take in items randomly with no particular order, but they are removed according to the priority of each element. If what I've said is true, wouldn't that mean that inserting any number of objects would be O(1) for both linked lists and arrays? If the PriorityQueue has no particular order, then wouldnt each add() simply insert something to the next array index/linked list node?
