-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathSolution.cs
More file actions
33 lines (32 loc) · 901 Bytes
/
Solution.cs
File metadata and controls
33 lines (32 loc) · 901 Bytes
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
/**
* Definition for a binary tree node.
* public class TreeNode {
* public int val;
* public TreeNode left;
* public TreeNode right;
* public TreeNode(int val=0, TreeNode left=null, TreeNode right=null) {
* this.val = val;
* this.left = left;
* this.right = right;
* }
* }
*/
public class Solution
{
public TreeNode BuildTree(int[] preorder, int[] inorder)
{
TreeNode root = new(preorder[0]);
int n = preorder.Length;
if (n == 1) return root;
int rootIndex = Array.IndexOf(inorder, preorder[0]);
if (rootIndex > 0)
{
root.left = BuildTree(preorder[1..(rootIndex + 1)], inorder[0..rootIndex]);
}
if (rootIndex < n - 1)
{
root.right = BuildTree(preorder[(rootIndex + 1)..], inorder[(rootIndex + 1)..]);
}
return root;
}
}