delets unnecessary file from the folder

02. Algorithms/10. LinkedList/Reverse LinkedList (Easy)/README.md

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+Leetcode Link: https://leetcode.com/problems/reverse-linked-list/ 
+
+To reverse a LinkedList, we need to reverse one node at a time.
+We will start with a variable current which will initially point to the head of the LinkedList
+and a variable previous which will point to the previous node that we have processed;
+initially previous will point to null.In a stepwise manner, we will reverse the current node by pointing
+it to the previous before moving on to the next node
+Also, we will update the previous to always point to the previous node that we have processed.
+
+ Here is visual representation of how previous is populated in each iteration
+Example: 4(head) -> 3 -> 0 -> 9
+1: previous = 4 -> null
+2: previous = 3 -> 4
+3: previous = 0 -> 3
+4: previous = 9 -> 0
+
+By the end of the iteration 9 is point to 0(9->0). if we go to 0's next field we get 3 and so on until null
+
+Time complexity
+ The time complexity of this algorithm will be O(N) where ‘N’ is the total number of nodes in the LinkedList.
+
+Space complexity 
+ I only used constant space, therefore, the space complexity of this algorithm is O(1)
+
+

02. Algorithms/10. LinkedList/Reverse LinkedList (Easy)/ReverseLinkedList.java

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+
+ /** Refer to the README to know how the algorithm works and to find the link for the question.
+ * @param node the head of the linked list
+ * @return the reversed linked list
+ */
+ public static ListNode reverseList(ListNode node) {
+ ListNode current = node; // stores the current node in the linked list
+ ListNode previous = null; // previous node that is processed
+ ListNode nextNode = null ; // a temporary node that will store the next node
+
+ while (current != null) {
+ nextNode = current.next; // temporarily stores the next node
+ current.next = previous; // reverse the current node
+ previous = current; // point previous to the current node
+ current = nextNode; // move to the next node
+ }
+
+ return previous; // returns the previous node which has the reversed list
+ }
+
+