Create linked list

Author: Barklim

2095-delete-the-middle-node-of-a-linked-list.js

@@ -24,19 +24,21 @@
  * @return {ListNode}
  */
 var deleteMiddle = function(head) {
-  let slow = new ListNode(0, head);
-  let fast = head;
-
-  if (!head.next) {
-    return null;
-  }
-
-  while (fast && fast.next) {
-    slow = slow.next;
-    fast = fast.next.next;
-  }
-
-  slow.next = slow.next.next;
-
-  return head;
+    // slow = head
+    // fast = head.next.next
+    let slow = new Node(0, null, head);
+    let fast = head;
+  
+    if (!head.next) {
+      return null;
+    }
+  
+    while (fast && fast.next) {
+      slow = slow.next;
+      fast = fast.next.next;
+    }
+  
+    slow.next = slow.next.next;
+  
+    return head;
 };

example/3.Linkedlist/0707.js

@@ -74,6 +74,9 @@ console.log(myLinkedList);
 console.log(myLinkedList.get(1)); // 3
 console.log(myLinkedList.get(2)); // -1
 console.log(myLinkedList.get(3)); // -1
+myLinkedList.addAtTail(4);
+console.log(myLinkedList.get(2)); // 2
+console.log(myLinkedList);
 
 
 // class Node {
@@ -184,3 +187,16 @@ console.log(myLinkedList.get(3)); // -1
 //     this.length--
 // };
 
+// MyLinkedList.prototype.toArray = function() {
+//     const nodes = [];
+
+//     let currentNode = this.head;
+//     while (currentNode) {
+//         nodes.push(currentNode.val);
+//         currentNode = currentNode.next;
+//     }
+
+//     return nodes;
+// };
+
+

example/3.Linkedlist/0876.js

@@ -0,0 +1,48 @@
+/**
+ * 876. Middle of the Linked List
+ * https://leetcode.com/problems/middle-of-the-linked-list/
+ * Difficulty: Easy
+ *
+ * Given the head of a singly linked list, return the middle node of the linked list.
+ *
+ * If there are two middle nodes, return the second middle node.
+ */
+
+/**
+ * Definition for singly-linked list.
+ * function ListNode(val, next) {
+ *     this.val = (val===undefined ? 0 : val)
+ *     this.next = (next===undefined ? null : next)
+ * }
+ */
+
+/**
+ * @param {ListNode} head
+ * @return {ListNode}
+ */
+var middleNode = function(head) {
+
+};
+
+const myLinkedList = new MyLinkedList();
+let head = myLinkedList.head;
+myLinkedList.addAtHead(1);
+myLinkedList.addAtTail(2);
+myLinkedList.addAtTail(3);
+
+console.log('middleNode');
+console.log(middleNode(head).val); // 1 2 3 // 2
+myLinkedList.addAtTail(4);
+console.log(middleNode(head).val); // 1 2 3 4 // 2
+myLinkedList.addAtTail(5);
+console.log(middleNode(head).val); // 12 3 45 // 3
+myLinkedList.addAtTail(6);
+console.log(middleNode(head).val); // 12 3 4 56 // 3
+myLinkedList.addAtTail(7);
+myLinkedList.addAtTail(8);
+console.log(middleNode(head).val); // 123 4 5 678 // 4
+myLinkedList.addAtTail(9);
+console.log(middleNode(head).val); // 1234 5 6789 // 5
+
+
+  

example/3.Linkedlist/2095.js

@@ -0,0 +1,56 @@
+/**
+ * 2095. Delete the Middle Node of a Linked List
+ * https://leetcode.com/problems/delete-the-middle-node-of-a-linked-list/
+ * Difficulty: Medium
+ *
+ * You are given the head of a linked list. Delete the middle node, and return the head
+ * of the modified linked list.
+ *
+ * The middle node of a linked list of size n is the ⌊n / 2⌋th node from the start using
+ * 0-based indexing, where ⌊x⌋ denotes the largest integer less than or equal to x.
+ *
+ * For n = 1, 2, 3, 4, and 5, the middle nodes are 0, 1, 1, 2, and 2, respectively.
+ */
+
+/**
+ * Definition for singly-linked list.
+ * function ListNode(val, next) {
+ *     this.val = (val===undefined ? 0 : val)
+ *     this.next = (next===undefined ? null : next)
+ * }
+ */
+/**
+ * @param {ListNode} head
+ * @return {ListNode}
+ */
+var deleteMiddle = function(head) {
+
+};
+
+const myLinkedList = new MyLinkedList();
+let head = myLinkedList.head;
+myLinkedList.addAtHead(1);
+myLinkedList.addAtTail(2);
+myLinkedList.addAtTail(3);
+myLinkedList.addAtTail(4);
+myLinkedList.addAtTail(5);
+myLinkedList.addAtTail(6);
+myLinkedList.addAtTail(7);
+
+console.log('deleteNode');
+console.log(myLinkedList.toArray().join(',')); 
+
+console.log('deleteNode 4');
+deleteMiddle(head) // 123 4 567 // 123 567
+console.log(myLinkedList.toArray().join(',')); 
+
+console.log('deleteNode 35'); // 12 3 5 67 // 12 5 67
+deleteMiddle(head)
+console.log(myLinkedList.toArray().join(','));
+
+console.log('deleteNode 3'); // 12 3 67 // 12 67
+deleteMiddle(head)
+console.log(myLinkedList.toArray().join(',')); 
+
+
+