22w7: add 108 js solution

Author: swiftwind0405

README.md

@@ -335,7 +335,7 @@
 |111|[Minimum Depth of Binary Tree](https://leetcode.com/problems/minimum-depth-of-binary-tree/)| [js](./algorithms/minimumDepthOfBinaryTree/minimumDepthOfBinaryTree.js) |Easy|
 |110|[Balanced Binary Tree](https://leetcode.com/problems/balanced-binary-tree/)| [java](./algorithms/balancedBinaryTree/Solution.java), [js](./algorithms/balancedBinaryTree/Solution.js)  |Easy|
 |109|[Convert Sorted List to Binary Search Tree](https://leetcode.com/problems/convert-sorted-list-to-binary-search-tree/)| |Medium|
-|108|[Convert Sorted Array to Binary Search Tree](https://leetcode.com/problems/convert-sorted-array-to-binary-search-tree/)| [Java](./algorithms/convertSortedArrayToBST/Solution.java) |Medium|
+|108|[Convert Sorted Array to Binary Search Tree](https://leetcode.com/problems/convert-sorted-array-to-binary-search-tree/)| [Java](./algorithms/convertSortedArrayToBST/Solution.java), [js](./algorithms/convertSortedArrayToBST/solution.js) |Medium|
 |107|[Binary Tree Level Order Traversal II](https://leetcode.com/problems/binary-tree-level-order-traversal-ii/)| |Easy|
 |106|[Construct Binary Tree from Inorder and Postorder Traversal](https://leetcode.com/problems/construct-binary-tree-from-inorder-and-postorder-traversal/)| |Medium|
 |105|[Construct Binary Tree from Preorder and Inorder Traversal](https://leetcode.com/problems/construct-binary-tree-from-preorder-and-inorder-traversal/)| |Medium|

algorithms/convertSortedArrayToBST/solution.js

@@ -0,0 +1,22 @@
+/**
+ * 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) {
+    if (!nums.length) return null;
+    // 取中间的索引
+    const middle = nums.length >> 1;
+    return new TreeNode(
+        nums[middle],                             // 根节点为中间节点
+        sortedArrayToBST(nums.slice(0, middle)),  // 左子树是左侧值
+        sortedArrayToBST(nums.slice(middle + 1)), // 右子树为右侧值
+    )
+};