From 42987012694e2370572ed30ff5ff6f201e613c02 Mon Sep 17 00:00:00 2001
From: markwang <www.wang61@qq.com>
Date: Tue, 16 Jul 2024 10:33:07 +0800
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---
 ...序与后序遍历序列构造二叉树.md | 108 ++++++++++++++++++
 1 file changed, 108 insertions(+)

diff --git a/problems/0106.从中序与后序遍历序列构造二叉树.md b/problems/0106.从中序与后序遍历序列构造二叉树.md
index 3518343f..bde61a75 100644
--- a/problems/0106.从中序与后序遍历序列构造二叉树.md
+++ b/problems/0106.从中序与后序遍历序列构造二叉树.md
@@ -794,6 +794,60 @@ func rebuild(inorder []int, postorder []int, rootIdx int, l, r int) *TreeNode {
 }
 ```
 
+```go
+/**
+ * Definition for a binary tree node.
+ * type TreeNode struct {
+ *     Val int
+ *     Left *TreeNode
+ *     Right *TreeNode
+ * }
+ */
+func buildTree(inorder []int, postorder []int) *TreeNode {
+    if len(postorder) == 0 {
+        return nil
+    }
+    
+    // 后序遍历数组最后一个元素，就是当前的中间节点
+    rootValue := postorder[len(postorder)-1]
+    root := &TreeNode{Val:rootValue}
+    
+    // 叶子结点
+    if len(postorder) == 1 {
+        return root
+    }
+    
+    // 找到中序遍历的切割点
+    var delimiterIndex int
+    for delimiterIndex = 0; delimiterIndex < len(inorder); delimiterIndex++ {
+        if inorder[delimiterIndex] == rootValue {
+            break;
+        }
+    }
+    
+    // 切割中序数组
+    // 左闭右开区间：[0, delimiterIndex)
+    leftInorder := inorder[:delimiterIndex]
+    // [delimiterIndex + 1, end)
+    rightInorder := inorder[delimiterIndex+1:]
+    
+    // postorder 舍弃末尾元素
+    postorder = postorder[:len(postorder)-1]
+    
+    // 切割后序数组
+    // 依然左闭右开，注意这里使用了左中序数组大小作为切割点
+    // [0, len(leftInorder))
+    leftPostorder := postorder[:len(leftInorder)]
+    // [len(leftInorder), end)
+    rightPostorder := postorder[len(leftInorder):]
+    
+    root.Left = buildTree(leftInorder, leftPostorder)
+    root.Right = buildTree(rightInorder, rightPostorder)
+    
+    return root
+}
+```
+
 105 从前序与中序遍历序列构造二叉树
 
 ```go
@@ -829,6 +883,60 @@ func build(pre []int, in []int, root int, l, r int) *TreeNode {
 }
 ```
 
+```go
+/**
+ * Definition for a binary tree node.
+ * type TreeNode struct {
+ *     Val int
+ *     Left *TreeNode
+ *     Right *TreeNode
+ * }
+ */
+func buildTree(preorder []int, inorder []int) *TreeNode {
+    if len(preorder) == 0 {
+        return nil
+    }
+    
+    // 前序遍历数组第一个元素，就是当前的中间节点
+    rootValue := preorder[0]
+    root := &TreeNode{Val:rootValue}
+    
+    // 叶子结点
+    if len(preorder) == 1 {
+        return root
+    }
+    
+    // 找到中序遍历的切割点
+    var delimiterIndex int
+    for delimiterIndex = 0; delimiterIndex < len(inorder); delimiterIndex++ {
+        if inorder[delimiterIndex] == rootValue {
+            break
+        }
+    }
+    
+    // 切割中序数组
+    // 左闭右开区间：[0, delimiterIndex)
+    leftInorder := inorder[:delimiterIndex]
+    // [delimiterIndex + 1, end)
+    rightInorder := inorder[delimiterIndex+1:]
+    
+    // preorder 舍弃首位元素
+    preorder = preorder[1:]
+    
+    // 切割前序数组
+    // 依然左闭右开，注意这里使用了左中序数组大小作为切割点
+    // [0, len(leftInorder))
+    leftPreorder := preorder[:len(leftInorder)]
+    // [len(leftInorder), end)
+    rightPreorder := preorder[len(leftInorder):]
+    
+    root.Left = buildTree(leftPreorder, leftInorder)
+    root.Right = buildTree(rightPreorder, rightInorder)
+    
+    return root
+}
+```
+
 
 ### JavaScript