with arrays its binary search which finds a value in O(Logn) time but what about linked lists ? the most effiecient algorithm will be O(n) ? and i know that binary search cannot be implement on a linked list , therefore , the only way to search a linked list is a linear search ?
View Repliesif one address point on another address. so set and get methods will be less efficient then an array, but add or remove will be more efficient by a linked list ? a linked list also inherit from queue so if i add an elemnt via "addFirst" function . where its adding the element ? to the right most or left most ?
if i have for example :
here [ ] --> [ ] --> [ ] --> [ ] -->[ ] or here
linked list its FIFO so the head will be the right most ?
Edit : its confused me a little bit but i understood now .so it will be at the left most. its actually ordered . not like the stack which is LIFO.
Ok here I have a code that generates 1 million random values then converts them to a string then hashcode. I then insert into a linked list and then I want to run through each hash and find it in the linked list timing each run then averaging out the time at the end.
It works great for smaller amounts of numbers it is searching for (fine under 50 thousand searches for the for loop starting at line 24 LinkedListTest.java) but when I try to do the full million searches it gives me "a Exception in thread "main" java.lang.StackOverflowError" at line 158 in List.java. Maybe im getting tired but I cannot figure out why.
// class to represent one node in a list
class ListNode< T >
{
// package access members; List can access these directly
T data; // data for this node
ListNode< T > nextNode; // reference to the next node in the list
[code]....
I need to display an object, which is in a linked list, given a vin number. It is the display_info method. Here is what i have so far:
import java.util.*;
public class Car implements Comparable<Car>, Cloneable
{
private String model;
private String color;
private int year;
private int vin_number;
private double price;
[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] ....
So recently I began Data Structures as core subject and the tutorials in this forum are great.
Right now, I seem to have trouble with Big Oh Notation algorithm and what is the mathematical side to it. "f(n) <= c.g(n), for n>=0.
The question I am working on is: Suppose we are maintaining a collection C of elements such that, each time we add a new element to the collection, we copy the contents of C into a new array list of just the right size. What is the running time of adding n elements to an initially empty collection C in this case?
Suppose i have written a method like this
public void myWork(){
mergeSortMyData(); O(nlgn)
....
someProcessing(); O(n^2)
someprocessing2(); O(n^2)
}
then what will be time complexity of my code...according to me it will be O(nlgn + n^2) ...is it correct ?
I can't able to find the theta for some type of code like.
for(i=1;i<=n;i++){
for(j=i;j>=1;j=j/3){
....
}
}
How to find the theta for the above code.
for(i=1;i<=n;i++){
for(j=i;j>=1;j=j/K){
....
}
}
and How to find number of steps or time complexity for inner loop if k=3 (odd)
I have a code that is meant to read a file and organize all the names from least to greatest salaries. It also allows the user to enter a name to find from the file, and the program finds the name and displays it. I have two errors, and I will show the error in my code
View Replies View RelatedI have some class called sorted to sort the linked list through the nodes of the list. and other class to test this ability, i made object of the sort class called "list1" and insert the values to the linked list.
If i make other object called "list2" and want to merge those two lists by using method merge in sort class. And wrote code of
list1.merge(list2);
How can the merge method in sort class know the values of list1 that called it as this object is created in other class.
An array which contain a list of names. I let for a user input and I use that to search through the array. For example lets say the string name "Christian" is stored inside the names array and the user types in Chri, the program looks in the array and finds a name that contains Chri and prints them out. How do I go about doing this?
View Replies View RelatedSo I need to be able to find the longest increasing sequence in a 2D grid of numbers. A sequence is simply a series of adjacent squares. Squares may not be used twice. Example here.
97 47 56 36 60 31 57 54 12 55
35 57 41 13 82 80 71 93 31 62
89 36 98 75 91 46 95 53 37 99
25 45 26 17 15 82 80 73 96 17
75 22 63 96 96 36 64 31 99 86
12 80 42 74 54 14 93 17 14 55
14 15 20 71 34 50 22 60 32 41
90 69 44 52 54 73 20 12 55 52
39 33 25 31 76 45 44 84 90 52
94 35 55 24 41 63 87 93 79 24
The longest sequence has length 10, consisting of entries (row, column) as follows;
(5,0) with cost 12
(6,0) with cost 14
(6,1) with cost 15
(6,2) with cost 20
(7,2) with cost 44
(7,3) with cost 52
(7,4) with cost 54
(6,3) with cost 71
(5,3) with cost 74
(4,3) with cost 96
I wouldn't be having a problem if I could use a 2D Array but the assignment requires the use of a List and StringTokenizer.
The way it works, a file is read and each row of the grid is an element of the List of Strings. So in the example above if I were to call myList.get(1) it would return 35 57 41 13 82 80 71 93 31 62 since it's the second row and second index value of the List.
If it was a 2D array I would check values at [x-1][x-1],[x-1][x]... to check all sides and diagonals ect ect. But with the List and Tokenizer there isn't a way that I know of that can search through the String using index values.
I wouldn't even know where to start with that. As of now I read the file fine and make the List of Strings and populate it properly, I'm just a little stuck. I should also mention that which ever method I use to search needs to be recursive.
This is what little I have. It reads in the file, creates the list and assigns the rows to the list.
import java.util.*;
import java.io.*;
public class MaxIncreasingSub {
public static void main(String []args) throws Exception{
File file = new File("Ass1Q2_test1");
List<String> myList = new ArrayList<String>();
[Code] .....
So we have an assignment regarding a linked list implementation of a given list interface.
In my list interface, the method contains(T anEntry) is defined.
In the LList implementation, contains is already implemented as part of getting the core methods in.
Now I am being tasked with the following:
Provide a second implementation of the method contains2(T anEntry) that calls a private recursive method
Private boolean contains (T anEntry, Node startNode) that returns whether the list that starts at startNode contains the entry anEntry.
I've written the private recursive method already. That's not an issue (at least not right now).
But what I don't understand is how startNode is supposed to be populated when this private contains method is called from the public contains2 method? contains2 only takes one parameter: anEntry. the private method takes two parameters: anEntry and startNode. How am i supposed to provide startNode when I am calling contains2?
I have an assignment for my intro class that requires me to read from a file that is a list of songs, their artists, and the year they were released. As seen below, a print line statement prompts the user to enter an artist name, and then it uses a buffered reader to gain input, and then it is supposed to match that input.I realize that this is not a complete statement, but I'm mostly concerned with getting the .indexOf statement to work.Currently it only returns the first object in the array.
for(int i = 0; i < song.length; i++) {
System.out.println("Enter an Artist name");
String input1 = kb.readLine();
if (song[i].getArtist().indexOf(input1) > -1) {
/*tried changing -1 to -2. When I do, it returns the
first array entry, regardless of what I input*/
System.out.println(song[i].toString());
}
}
I have a list of 100,000 + names and I need to append to that list another 100,000 names. Each name must be unique. Currently I iterate through the entire list to be sure the name does not exist. As you can imagine this is very slow. I am new to Java and I am maintaining a 15+ year old product. Is there a better way to check for an existing name?
View Replies View RelatedI have this ListInterface class that has operations for my linked list and a LList class. The Llist and ListInterface classes are perfect. My job is to create a driver, or a demo class that showcases these operations. That being said, heres the driver so far:
import java.util.*;
public abstract class DriverWilson implements ListInterface
{
public static void main(String[] args)
{
LList a = new LList();
[code]....
What I'm supposed to do is make a method to insert a set of Tiles to the list,i.e.,a detour(make sure that the inserted detouris compatible with thecurrent path so that the resultingpathdoesnot have any gaps). But I'm confused on how to go about doing it. I was thinking of maybe just adding 1 to the current Node.
import java.io.File;
import java.io.FileNotFoundException;
import java.util.List;
import java.util.Scanner;
public class Path {
static Tile startTile;
[code].....
I'm trying to implement an Office class that contains an inner class: WorkerNode. The WorkerNode class has a name attribute (String) and WorkerNode attributes for boss, peer and subordinate. The attributes of Office are manager and current which are WorkerNode references. The manager refers to the entry point of the structure and current is the current node in the structure. For simplicity, i'm going to try to limit it to 3 levels and assume that the names are unique. I've put together a Office class that containing main and provided the code I've worked on so far.
public class Office {
public static void main(String[] args) {
String name=Input.getString("input the manager's name: ");
Office office=new Office(name);
int option;
[code]....
I have made a node class and im trying to implement a sorting method. I must use a selection sort but with specific instructions: "Your method should not need to use the new operator since it is just moving nodes from one list to another( not creating new nodes)
this is my current implementation ..but i am instantiating new object..
public class NodeInt
{
private int data;
private NodeInt next = null;
public NodeInt(){}
//precondition:
//postcondition:
public NodeInt(int data, NodeInt next)
{
this.data = data;
this.next = next;
[code]....
edit: this is the part that worked but i had it commented out so i have the previous and current declared above but didnt copy.
public void add(int d){
listNode l = new listNode (d, null);
l.next = first;
first= l;
}
public list Sum2List (list l1, list l2){
//variables
int sum;
[Code] .....
But I have a problem in my first listNode where it ll be pointing to null, thus in the sum2List method the program checks the while condition into false and doesn't go through the loop.
I searched a lot but can't seem to understand the sorting of a SLLNode... I noticed a method called Bubble Sort, I understand how it works, but can't think of a way to implement it to my code..
View Replies View RelatedIs there a particular implementation of a linked list you are referring to in your question?
View Replies View RelatedI'm having some trouble with figuring out how to move along a doubly linked list for an assignment. The program is supposed to be a simple board game simulation. Here is what I have so far:
Space.java:
public class Space
{
private String name;
public Space next;
public Space previous;
public Space(String name)
{
this.name = name;
[Code]...
I seem to have been able to get all the other methods working properly, but I am pretty stuck on how to do the movePlayer. Specifically because it is passing an integer, but my objects are of type Space and Boardgame.
i tried everything but its giving me errors. i tried the for loop but its giving me something else.
this is what i have to do Write a recursive method that prints out the data elements of a linked list in reverse order.
Your method should take in as a parameter the head reference to a linked list. Then, write a recursive method that returns a count of the number of elements greater than a given threshold. You may assume that the data elements in the linked lists are ints. The parameters of your method are a reference to the linked list and a int value representing the threshold.
public class recursion3
{
public static void main(String [] args) {
char a [] = {'A', 'B','C','D','E'};
System.out.println(a);
}
public static String reverseString(String s) {
if (s.length() <= 1) {
[code]....
I'm trying to print the contents of my linked list. I'm using nodes and within those nodes it hold String data. So i want to print out the data within the nodes. Whenever i do
System.out.println(node1.data),
it prints perfectly. But i'm trying to use a method where it would loop through the list and print out the data for every node in it. when i run my print method i get results such as
Node@15db9742
Node@6d06d69c
Node@7852e922.
Here is my print method i created
Java Code:
public void print(){
Node<E> current = head;
while (current.next != null){
System.out.println(current.data);
current = current.next;
}
} mh_sh_highlight_all('java');
I am creating a recursive method to reverse a linked list in java. It works the first time when I call it, but I want it to work where I call it a second time and it reverses it to the original state. How can I get that to work with this implementation?
public void reverseList() {
System.out.printf("%-16s%-3s%n", "Name", "Score");
System.out.println("--------------- -----");
reverseList(first);
} public void reverseList(Node aNode) {
if (aNode != null) {
reverseList(aNode.next);
System.out.printf("%-15s%6s%n" , aNode.name , aNode.score);
}
}