Merge pull request #463 from kok-s0s/master

提供二叉树部分的JavaScript代码

problems/0108.将有序数组转换为二叉搜索树.md

@@ -350,6 +350,36 @@ func sortedArrayToBST(nums []int) *TreeNode {
 }
 ```
 
+JavaScript版本
+
+```javascript
+/**
+ * Definition for a binary tree node.
+ * function TreeNode(val, left, right) {
+ *     this.val = (val===undefined ? 0 : val)
+ *     this.left = (left===undefined ? null : left)
+ *     this.right = (right===undefined ? null : right)
+ * }
+ */
+/**
+ * @param {number[]} nums
+ * @return {TreeNode}
+ */
+var sortedArrayToBST = function (nums) {
+    const buildTree = (Arr, left, right) => {
+        if (left > right)
+            return null;
+
+        let mid = Math.floor(left + (right - left) / 2);
+
+        let root = new TreeNode(Arr[mid]);
+        root.left = buildTree(Arr, left, mid - 1);
+        root.right = buildTree(Arr, mid + 1, right);
+        return root;
+    }
+    return buildTree(nums, 0, nums.length - 1);
+};
+```
 
 
 

problems/0538.把二叉搜索树转换为累加树.md

@@ -239,7 +239,70 @@ func RightMLeft(root *TreeNode,sum *int) *TreeNode {
 }
 ```
 
+JavaScript版本
 
+> 递归
+
+```javascript
+/**
+ * Definition for a binary tree node.
+ * function TreeNode(val, left, right) {
+ *     this.val = (val===undefined ? 0 : val)
+ *     this.left = (left===undefined ? null : left)
+ *     this.right = (right===undefined ? null : right)
+ * }
+ */
+/**
+ * @param {TreeNode} root
+ * @return {TreeNode}
+ */
+var convertBST = function(root) {
+    let pre = 0;
+    const ReverseInOrder = (cur) => {
+        if(cur) {
+            ReverseInOrder(cur.right);
+            cur.val += pre;
+            pre = cur.val;
+            ReverseInOrder(cur.left);
+        }
+    }
+    ReverseInOrder(root);
+    return root;
+};
+```
+
+> 迭代
+
+```javascript
+/**
+ * Definition for a binary tree node.
+ * function TreeNode(val, left, right) {
+ *     this.val = (val===undefined ? 0 : val)
+ *     this.left = (left===undefined ? null : left)
+ *     this.right = (right===undefined ? null : right)
+ * }
+ */
+/**
+ * @param {TreeNode} root
+ * @return {TreeNode}
+ */
+var convertBST = function (root) {
+    let pre = 0;
+    let cur = root;
+    let stack = [];
+    while (cur !== null || stack.length !== 0) {
+        while (cur !== null) {
+            stack.push(cur);
+            cur = cur.right;
+        }
+        cur = stack.pop();
+        cur.val += pre;
+        pre = cur.val;
+        cur = cur.left;
+    }
+    return root;
+};
+```
 
 -----------------------
 * 作者微信：[程序员Carl](https://mp.weixin.qq.com/s/b66DFkOp8OOxdZC_xLZxfw)