提交 《从前序与中序遍历序列构造二叉树》JavaScript版本的代码

problems/0106.从中序与后序遍历序列构造二叉树.md

@@ -775,6 +775,20 @@ var buildTree = function(inorder, postorder) {
 };
 ```
 
+从前序与中序遍历序列构造二叉树
+
+```javascript
+var buildTree = function(preorder, inorder) {
+    if(!preorder.length)
+        return null;
+    let root = new TreeNode(preorder[0]);
+    let mid = inorder.findIndex((number) => number === root.val);
+    root.left = buildTree(preorder.slice(1, mid + 1), inorder.slice(0, mid));
+    root.right = buildTree(preorder.slice(mid + 1, preorder.length), inorder.slice(mid + 1, inorder.length));
+    return root;
+};
+```
+
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 * 作者微信：[程序员Carl](https://mp.weixin.qq.com/s/b66DFkOp8OOxdZC_xLZxfw)
 * B站视频：[代码随想录](https://space.bilibili.com/525438321)