From 82b16a00260076e4781f0b567ad6085c38d2385c Mon Sep 17 00:00:00 2001
From: Omooo <869759698@qq.com>
Date: Thu, 2 Jul 2020 09:29:44 +0800
Subject: [PATCH] =?UTF-8?q?Update=20=E4=BA=8C=E5=8F=89=E6=A0=91=E7=9B=B8?=
 =?UTF-8?q?=E5=85=B3.md?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../Algorithm/剑指 Offer/二叉树相关.md | 32 +++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/blogs/Algorithm/剑指 Offer/二叉树相关.md b/blogs/Algorithm/剑指 Offer/二叉树相关.md
index 18d0997..b78ff77 100644
--- a/blogs/Algorithm/剑指 Offer/二叉树相关.md	
+++ b/blogs/Algorithm/剑指 Offer/二叉树相关.md	
@@ -33,3 +33,35 @@ class Solution {
 }
 ```
 
+```java
+class Solution {
+
+    public TreeNode buildTree(int[] preorder, int[] inorder) {
+        if (preorder == null || preorder.length == 0) {
+            return null;
+        }
+        TreeNode root = new TreeNode(preorder[0]);
+        int length = preorder.length;
+        Stack<TreeNode> stack = new Stack<>();
+        stack.push(root);
+        int inorderIndex = 0;
+        for (int i = 1; i < length; i++) {
+            int preorderVal = preorder[i];
+            TreeNode node = stack.peek();
+            if (node.val != inorder[inorderIndex]) {
+                node.left = new TreeNode(preorderVal);
+                stack.push(node.left);
+            } else {
+                while (!stack.isEmpty() && stack.peek().val == inorder[inorderIndex]) {
+                    node = stack.pop();
+                    inorderIndex++;
+                }
+                node.right = new TreeNode(preorderVal);
+                stack.push(node.right);
+            }
+        }
+        return root;
+    }
+}
+```
+