package com.thealgorithms.datastructures.lists;
import java.util.ArrayList;
import java.util.List;
/**
* A SortedLinkedList is a data structure that maintains a sorted list of elements.
* Elements are ordered based on their natural ordering or by a Comparator provided at the time of creation.
* This implementation uses a singly linked list to store the elements.
* Further details can be found on this link
* https://runestone.academy/ns/books/published/cppds/LinearLinked/ImplementinganOrderedList.html
*/
public class SortedLinkedList {
private Node head;
private Node tail;
public SortedLinkedList() {
this.head = null;
this.tail = null;
}
/**
* Inserts a new element into the sorted linked list.
* @param value the value to be inserted
*/
public void insert(int value) {
Node newNode = new Node(value);
if (head == null) {
this.head = newNode;
this.tail = newNode;
} else if (value < head.value) {
newNode.next = this.head;
this.head = newNode;
} else if (value > tail.value) {
this.tail.next = newNode;
this.tail = newNode;
} else {
Node temp = head;
while (temp.next != null && temp.next.value < value) {
temp = temp.next;
}
newNode.next = temp.next;
temp.next = newNode;
if (newNode.next == null) {
this.tail = newNode;
}
}
}
/**
* Displays the elements of the sorted linked list.
*/
public void display() {
System.out.println(this.toString());
}
/**
* Deletes the first occurrence of the specified element in the sorted linked list.
* @param value the value to be deleted
* @return true if the element is found and deleted, false otherwise
*/
public boolean delete(int value) {
if (this.head == null) {
return false;
} else if (this.head.value == value) {
if (this.head.next == null) {
this.head = null;
this.tail = null;
} else {
this.head = this.head.next;
}
return true;
} else {
Node temp = this.head;
while (temp.next != null) {
if (temp.next.value == value) {
if (temp.next == this.tail) {
this.tail = temp;
}
temp.next = temp.next.next;
return true;
}
temp = temp.next;
}
return false;
}
}
/**
* Searches for the specified element in the sorted linked list.
* @param value the value to be searched
* @return true if the element is found, false otherwise
*/
public boolean search(int value) {
Node temp = this.head;
while (temp != null) {
if (temp.value == value) {
return true;
}
temp = temp.next;
}
return false;
}
/**
* Checks if the sorted linked list is empty.
* @return true if the list is empty, false otherwise
*/
public boolean isEmpty() {
return head == null;
}
/**
* Returns a string representation of the sorted linked list.
* @return a string representation of the sorted linked list
*/
@Override
public String toString() {
if (this.head != null) {
List<String> elements = new ArrayList<>();
Node temp = this.head;
while (temp != null) {
elements.add(String.valueOf(temp.value));
temp = temp.next;
}
return "[" + String.join(", ", elements) + "]";
} else {
return "[]";
}
}
public final class Node {
public final int value;
public Node next;
public Node(int value) {
this.value = value;
this.next = null;
}
}
}