From 4968dfb1f0de354b6d2fdf5b2e688874c3df4604 Mon Sep 17 00:00:00 2001
From: Antesh Sharma <anteshsharma642@gmail.com>
Date: Wed, 16 Feb 2022 22:20:28 +0530
Subject: [PATCH] Added solution to find loop in linkedlist

---
 .../com/antesh/dsa/ArrayToLinkedList.java     |  2 -
 .../nvidia/FindLoopInLinkedList.java          | 65 +++++++++++++++++++
 2 files changed, 65 insertions(+), 2 deletions(-)
 create mode 100644 src/main/java/com/antesh/interview/nvidia/FindLoopInLinkedList.java

diff --git a/src/main/java/com/antesh/dsa/ArrayToLinkedList.java b/src/main/java/com/antesh/dsa/ArrayToLinkedList.java
index 691a7e4..3fce1b4 100644
--- a/src/main/java/com/antesh/dsa/ArrayToLinkedList.java
+++ b/src/main/java/com/antesh/dsa/ArrayToLinkedList.java
@@ -48,8 +48,6 @@ public static Node insertUsingWhileLoop(Node root, int data) {
         if (root == null) {
             root = temp;
         } else {
-
-
             Node ptr = root;
             while (ptr.next != null) {
                 ptr = ptr.next;
diff --git a/src/main/java/com/antesh/interview/nvidia/FindLoopInLinkedList.java b/src/main/java/com/antesh/interview/nvidia/FindLoopInLinkedList.java
new file mode 100644
index 0000000..5367d39
--- /dev/null
+++ b/src/main/java/com/antesh/interview/nvidia/FindLoopInLinkedList.java
@@ -0,0 +1,65 @@
+package com.antesh.interview.nvidia;
+
+/*
+ * Goal is to find the loop in LinkedList without extra space
+ * */
+
+public class FindLoopInLinkedList {
+
+    public static Node root;
+
+    public static Node insertNode(Node root, int data) {
+        Node temp = new Node();
+        temp.data = data;
+        temp.next = null;
+
+        if (root == null) {
+            root = temp;
+        } else {
+            Node ptr = root;
+            while (ptr.next != null) {
+                ptr = ptr.next;
+            }
+            ptr.next = temp;
+        }
+        return root;
+    }
+
+    public static boolean detectLoop() {
+        Node p_slow = root;
+        Node p_fast = root;
+
+        while (p_slow != null && p_fast != null && p_fast.next != null) {
+            p_slow = p_slow.next;
+            p_fast = p_fast.next.next;
+            if (p_fast == p_slow) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    public static void print(Node root) {
+        while (root != null) {
+            System.out.print(root.data + " -> ");
+            root = root.next;
+        }
+        System.out.println();
+    }
+
+    //driver
+    public static void main(String[] args) {
+        int[] arr = new int[]{5, 25, 10, 35, 40};
+        for (int num : arr) {
+            root = insertNode(root, num);
+        }
+
+        print(root);
+        System.out.println("Is Loop present in LinkedList? \nAns: " + detectLoop());
+    }
+
+    static class Node {
+        int data;
+        Node next;
+    }
+}