From 0ed113487080dd4cf99d3048863f67c267af96aa Mon Sep 17 00:00:00 2001
From: eeee0717 <chentao020717Work@outlook.com>
Date: Sun, 3 Dec 2023 09:41:53 +0800
Subject: [PATCH 1/2] =?UTF-8?q?Update=200501.=E4=BA=8C=E5=8F=89=E6=90=9C?=
 =?UTF-8?q?=E7=B4=A2=E6=A0=91=E4=B8=AD=E7=9A=84=E4=BC=97=E6=95=B0=EF=BC=8C?=
 =?UTF-8?q?=E6=B7=BB=E5=8A=A0C#=E7=89=88?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 problems/0501.二叉搜索树中的众数.md | 40 ++++++++++++++++++++
 1 file changed, 40 insertions(+)

diff --git a/problems/0501.二叉搜索树中的众数.md b/problems/0501.二叉搜索树中的众数.md
index 8881200f..5b26d580 100644
--- a/problems/0501.二叉搜索树中的众数.md
+++ b/problems/0501.二叉搜索树中的众数.md
@@ -1009,6 +1009,46 @@ pub fn find_mode(root: Option<Rc<RefCell<TreeNode>>>) -> Vec<i32> {
         res
     }
 ```
+### C#
+```C#
+// 递归 
+public class Solution
+{
+    public List<int> res = new List<int>();
+    public int count = 0;
+    public int maxCount = 0;
+    public TreeNode pre = null;
+    public int[] FindMode(TreeNode root)
+    {
+        SearchBST(root);
+        return res.ToArray();
+    }
+    public void SearchBST(TreeNode root)
+    {
+        if (root == null) return;
+        SearchBST(root.left);
+        if (pre == null)
+            count = 1;
+        else if (pre.val == root.val)
+            count++;
+        else
+            count = 1;
+
+        pre = root;
+        if (count == maxCount)
+        {
+            res.Add(root.val);
+        }
+        else if (count > maxCount)
+        {
+            res.Clear();
+            res.Add(root.val);
+            maxCount = count;
+        }
+        SearchBST(root.right);
+    }
+}
+```
 
 
 <p align="center">

From a0e2c5ceb06d9199bc6f2ce2eb0aa87a8ebf8fe4 Mon Sep 17 00:00:00 2001
From: eeee0717 <chentao020717Work@outlook.com>
Date: Mon, 4 Dec 2023 09:42:53 +0800
Subject: [PATCH 2/2] =?UTF-8?q?Update0236.=E4=BA=8C=E5=8F=89=E6=A0=91?=
 =?UTF-8?q?=E7=9A=84=E6=9C=80=E8=BF=91=E5=85=AC=E5=85=B1=E7=A5=96=E5=85=88?=
 =?UTF-8?q?=EF=BC=8C=E6=8F=90=E4=BA=A4C#=E7=89=88?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 problems/0236.二叉树的最近公共祖先.md | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/problems/0236.二叉树的最近公共祖先.md b/problems/0236.二叉树的最近公共祖先.md
index edb5ea3e..0e99f1c2 100644
--- a/problems/0236.二叉树的最近公共祖先.md
+++ b/problems/0236.二叉树的最近公共祖先.md
@@ -431,6 +431,19 @@ impl Solution {
     }
 }
 ```
+### C#
+```C#
+public TreeNode LowestCommonAncestor(TreeNode root, TreeNode p, TreeNode q)
+{
+    if (root == null || root == p || root == q) return root;
+    TreeNode left = LowestCommonAncestor(root.left, p, q);
+    TreeNode right = LowestCommonAncestor(root.right, p, q);
+    if (left != null && right != null) return root;
+    if (left == null && right != null) return right;
+    if (left != null && right == null) return left;
+    return null;
+}
+```
 
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