add js solution for leetcode 83 144 237

Author: swiftwind0405

README.md

@@ -195,7 +195,7 @@
 |240|[Search a 2D Matrix II](https://leetcode.com/problems/search-a-2d-matrix-ii/)||Medium|
 |239|[Sliding Window Maximum](https://leetcode.com/problems/sliding-window-maximum/)| |Hard|
 |238|[Product of Array Except Self](https://leetcode.com/problems/product-of-array-except-self/)| |Medium|
-|237|[ Node in a Linked List](https://leetcode.com/problems/-node-in-a-linked-list/)| |Easy|
+|237|[Node in a Linked List](https://leetcode.com/problems/-node-in-a-linked-list/)| [js](./algorithms/nodeInALinkedList/nodeInALinkedList.js) |Easy|
 |236|[Lowest Common Ancestor of a Binary Tree](https://leetcode.com/problems/lowest-common-ancestor-of-a-binary-tree/)| |Medium|
 |235|[Lowest Common Ancestor of a Binary Search Tree](https://leetcode.com/problems/lowest-common-ancestor-of-a-binary-search-tree/)| |Easy|
 |234|[Palindrome Linked List](https://leetcode.com/problems/palindrome-linked-list/)| |Easy|
@@ -282,7 +282,7 @@
 |147|[Insertion Sort List](https://leetcode.com/problems/insertion-sort-list/)| |Medium|
 |146|[LRU Cache](https://leetcode.com/problems/lru-cache/)| |Hard|
 |145|[Binary Tree Postorder Traversal](https://leetcode.com/problems/binary-tree-postorder-traversal/)| |Hard|
-|144|[Binary Tree Preorder Traversal](https://leetcode.com/problems/binary-tree-preorder-traversal/)| |Medium|
+|144|[Binary Tree Preorder Traversal](https://leetcode.com/problems/binary-tree-preorder-traversal/)| [js](./algorithms/binaryTreePreorderTraversal/binaryTreePreorderTraversal.js) |Medium|
 |143|[Reorder List](https://leetcode.com/problems/reorder-list/)| |Medium|
 |142|[Linked List Cycle II](https://leetcode.com/problems/linked-list-cycle-ii/)| |Medium|
 |141|[Linked List Cycle](https://leetcode.com/problems/linked-list-cycle/)| |Medium|
@@ -343,7 +343,7 @@
 |86|[Partition List](https://leetcode.com/problems/partition-list/)| |Medium|
 |85|[Maximal Rectangle](https://leetcode.com/problems/maximal-rectangle/)| |Hard|
 |84|[Largest Rectangle in Histogram](https://leetcode.com/problems/largest-rectangle-in-histogram/)| |Hard|
-|83|[Remove Duplicates from Sorted List](https://leetcode.com/problems/remove-duplicates-from-sorted-list/)| |Easy|
+|83|[Remove Duplicates from Sorted List](https://leetcode.com/problems/remove-duplicates-from-sorted-list/)| [js](./algorithms/removeDuplicatesFromSortedList/removeDuplicatesFromSortedList.js)  |Easy|
 |82|[Remove Duplicates from Sorted List II](https://leetcode.com/problems/remove-duplicates-from-sorted-list-ii/)| |Medium|
 |81|[Search in Rotated Sorted Array II](https://leetcode.com/problems/search-in-rotated-sorted-array-ii/)| |Medium|
 |80|[Remove Duplicates from Sorted Array II](https://leetcode.com/problems/remove-duplicates-from-sorted-array-ii/)| |Medium|

algorithms/binaryTreePreorderTraversal/binaryTreePreorderTraversal.js

@@ -0,0 +1,5 @@
+var deleteNode = function(node) {
+    // 传入的就是要删除的节点，因此把它用下个节点覆盖即可
+    node.val = node.next.val;
+    node.next = node.next.next;
+};

algorithms/nodeInALinkedList/nodeInALinkedList.js

@@ -0,0 +1,11 @@
+var deleteDuplicates = function (head) {
+    let p = head;
+    while (p && p.next) {
+        if (p.val === p.next.val) {
+            p.next = p.next.next;
+        } else {
+            p = p.next;
+        }
+    }
+    return head;
+};