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Fix incorrect file extension (Fixes: #2716) (#2717)

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Shivam Shrey 2021-10-28 00:26:00 +05:30 committed by GitHub
parent 64513ff53e
commit 9b90628a89
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3 changed files with 96 additions and 108 deletions
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95
DataStructures/Lists/CreateAndDetectLoop.java Normal file
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@ -0,0 +1,95 @@
package DataStructures.Lists;
import java.util.Scanner;
public class CreateAndDetectLoop {
/**
* Prints the linked list.
*
* @param head head node of the linked list
*/
static void printList(Node head) {
Node cur = head;
while (cur != null) {
System.out.print(cur.value + " ");
cur = cur.next;
}
}
/**
* Creates a loop in the linked list.
* @see <a href="https://www.geeksforgeeks.org/make-loop-k-th-position-linked-list/">
* GeeksForGeeks: Make a loop at K-th position</a>
* @param head head node of the linked list
* @param k position of node where loop is to be created
*/
static void createLoop(Node head, int k) {
if (head == null)
return;
Node temp = head;
int count = 1;
while (count < k) { // Traverse the list till the kth node
temp = temp.next;
count++;
}
Node connectedPoint = temp;
while (temp.next != null) // Traverse remaining nodes
temp = temp.next;
temp.next = connectedPoint; // Connect last node to k-th element
}
/**
* Detects the presence of a loop in the linked list.
* @see <a href="https://en.wikipedia.org/wiki/Cycle_detection#Floyd's_tortoise_and_hare">
* Floyd's Cycle Detection Algorithm</a>
*
* @param head the head node of the linked list
*
* @return true if loop exists else false
*/
static boolean detectLoop(Node head) {
Node sptr = head;
Node fptr = head;
while (fptr != null && fptr.next != null) {
sptr = sptr.next;
fptr = fptr.next.next;
if (fptr == sptr)
return true;
}
return false;
}
public static void main(String[] args) {
SinglyLinkedList singlyLinkedList = new SinglyLinkedList();
Scanner sc = new Scanner(System.in);
System.out.println("Enter the number of elements to be inserted: ");
int n = sc.nextInt();
System.out.printf("Enter the %d elements: \n", n);
while (n-- > 0)
singlyLinkedList.insert(sc.nextInt());
System.out.print("Given list: ");
printList(singlyLinkedList.getHead());
System.out.println();
System.out.println("Enter the location to generate loop: ");
int k = sc.nextInt();
createLoop(singlyLinkedList.getHead(), k);
if (detectLoop(singlyLinkedList.getHead()))
System.out.println("Loop found");
else
System.out.println("No loop found");
sc.close();
}
}

2
DataStructures/Lists/README.md
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@ -25,6 +25,6 @@ The `next` variable points to the next node in the data structure and value stor
1. `CircleLinkedList.java` : A circular linked list where next pointer of last node points to first nide of linked list.
2. `SinglyLinkedList.java` : The classic case of single links.
3. `CountSinglyLinkedListRecursion.java`: Recursively counts the size of a list.
4. `detect_and_create_loop.java` : Detect a loop in linked list
4. `CreateAndDetectLoop.java` : Create and detect a loop in a linked list.
5. `DoublyLinkedList.java` : A modification of singly linked list which has a `prev` pointer to point to the previous node.
6. `Merge_K_SortedLinkedlist.java` : Merges K sorted linked list with mergesort (mergesort is also the most efficient sorting algorithm for linked list).

107
DataStructures/Lists/detect_and_create_loop.jav
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@ -1,107 +0,0 @@
import java.util.*;
import java.util.Scanner;
public class LinkedList {
static Node head; // head of list
static class Node // Linked list Node
{
int data; //to store value
Node next; //pointer
Node(int d) {
data = d;
next = null;
}
}
static int countNodes(Node ptr) //Function to count the number of nodes present
{
int count = 0;
while (ptr != null) {
ptr = ptr.next;
count++;
}
return count;
}
static public void push(int new_data) // Function to inserts a new Node at front of the list
{
Node new_node = new Node(new_data); //Allocate a pointer/node and store the data
new_node.next = head; // make next of new Node as head
head = new_node; // Move the head to point to new Node.
}
static void printList(Node head, int total_nodes) //function to traverse through the list and print all data values
{
Node curr = head;
int count = 0;
while (count < total_nodes) {
count++;
System.out.print(curr.data + " ");
curr = curr.next;
}
}
static Node makeloop(Node head_ref, int k) {
Node temp = head_ref;
int count = 1;
while (count < k) //traverrse the list till point is found
{
temp = temp.next;
count++;
}
Node connected_point = temp;
while (temp.next != null) // traverse remaining nodes
temp = temp.next;
temp.next = connected_point; //connect last node to k-th element
return head_ref;
}
static boolean detectLoop(Node h) //Function to detect loop, retuens true if loop is in linked list else returns false.
{
HashSet < Node > traverse = new HashSet < Node > ();
while (n != null) {
if (traverse.contains(n)) //if the hash a;ready contains a record of the node encountered true is returned as a loop isdetected
return true;
traverse.add(n);
n = n.next;
}
return false;
}
public static void main(String[] args) {
LinkedList l = new LinkedList();
Scanner sc = new Scanner(System.in);
print("Enter elements in the list, to stop entering press any alphabetical key");
while (true) {
try {
i = sc.nextInt();
l.push(i);
} catch (Exception e) {
System.out.println("Creating loop for run");
}
}
System.out.println("Enter the location to generate loop");
int k = sc.nextInt()
System.out.print("Given list");
printList(head, total_nodes);
head = makeloop(head, k);
System.out.print("Modified list with loop");
printList(head, total_nodes);
if (detectLoop(head))
System.out.println("Loop found");
else
System.out.println("No Loop");
}
}