diff --git a/problems/3025-find-the-number-of-ways-to-place-people-i/README.md b/problems/3025-find-the-number-of-ways-to-place-people-i/README.md
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+# [3025] Find The Number Of Ways To Place People I
+
+## 題目資訊
+- **難度**: Medium
+- **標籤**: Array, Math, Geometry, Sorting, Enumeration
+- **題目連結**: [LeetCode](https://leetcode.com/problems/find-the-number-of-ways-to-place-people-i/)
+- **練習日期**: 2025-09-02
+
+## 題目描述
+You are given a 2D array `points` of size `n x 2` representing integer coordinates of some points on a 2D plane, where `points[i] = [xi, yi]`.
+
+Count the number of pairs of points `(A, B)`, where
+ - `A` is on **the upper** left side of `B`, and
+ - there are no other points in the rectangle (or line) they make (**including the border**).
+
+Return the count.
+
+## 解題思路
+
+### 初步分析
+- 這題主要考察什麼概念？
+- 有什麼關鍵限制條件？
+- 預期時間/空間複雜度？
+
+### 解法概述
+1. **暴力解法**:
+ - 思路：
+ - 時間複雜度：O(?)
+ - 空間複雜度：O(?)
+
+2. **優化解法**:
+ - 思路：
+ - 時間複雜度：O(?)
+ - 空間複雜度：O(?)
+
+## 測試案例
+
+### 範例輸入輸出
+```
+Input: points = [[6,2],[4,4],[2,6]]
+Output: 2
+Explanation:
+ - The left one is the pair (points[1], points[0]), where points[1] is on the upper left side of points[0] and the rectangle is empty.
+ - The left one is the pair (points[1], points[0]), where points[1] is on the upper left side of points[0] and the rectangle is empty.
+ - The right one is the pair (points[2], points[0]), where points[2] is on the upper left side of points[0], but points[1] is inside the rectangle so it's not a valid pair.
+```
+
+### 邊界情況
+- `2 <= n <= 50`
+- `points[i].length == 2`
+- `0 <= points[i][0], points[i][1] <= 50`
+- All `points[i]` are distinct.
+
+## 學習筆記
+
+### 今天學到什麼？
+-
+
+### 遇到的困難
+-
+
+### 改善方向
+-
+
+### 相關題目
+- [題目編號] 題目名稱 - 相似概念
+- [題目編號] 題目名稱 - 進階版本
+
+---
+**總結**: 這題的核心概念是...，適合練習...技巧。
diff --git a/problems/3025-find-the-number-of-ways-to-place-people-i/csharp/Program.cs b/problems/3025-find-the-number-of-ways-to-place-people-i/csharp/Program.cs
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+++ b/problems/3025-find-the-number-of-ways-to-place-people-i/csharp/Program.cs
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+// LeetCode 3025: Find The Number Of Ways To Place People I
+// 難度: Medium
+// 日期: 2025-09-02
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+
+public class Solution {
+ public void Solve() {
+ // TODO: 實作解法
+ Console.WriteLine("Hello LeetCode 3025!");
+ }
+}
+
+// 測試程式
+public class Program {
+ public static void Main() {
+ Solution sol = new Solution();
+ sol.Solve();
+
+ // TODO: 加入測試案例
+ // TestCase1();
+ // TestCase2();
+ }
+
+ // 測試案例模板
+ /*
+ static void TestCase1() {
+ // Input:
+ // Expected:
+ // Actual:
+ Console.WriteLine("Test 1: ");
+ }
+ */
+}
diff --git a/problems/3025-find-the-number-of-ways-to-place-people-i/csharp/csharp.csproj b/problems/3025-find-the-number-of-ways-to-place-people-i/csharp/csharp.csproj
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+++ b/problems/3025-find-the-number-of-ways-to-place-people-i/csharp/csharp.csproj
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+
+
+
+ Exe
+ net8.0
+ enable
+ enable
+
+
+
diff --git a/problems/3025-find-the-number-of-ways-to-place-people-i/test/SolutionTests.cs b/problems/3025-find-the-number-of-ways-to-place-people-i/test/SolutionTests.cs
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+++ b/problems/3025-find-the-number-of-ways-to-place-people-i/test/SolutionTests.cs
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+// LeetCode 3025 單元測試
+// 使用 xUnit 框架
+
+using Xunit;
+using System;
+using System.Collections.Generic;
+
+public class SolutionTests {
+ private readonly Solution _solution;
+
+ public SolutionTests() {
+ _solution = new Solution();
+ }
+
+ [Fact]
+ public void TestCase1() {
+ // Arrange
+ // TODO: 設定輸入資料
+ // var input = ;
+ // var expected = ;
+
+ // Act
+ // var result = _solution.YourMethod(input);
+
+ // Assert
+ // Assert.Equal(expected, result);
+
+ Assert.True(true); // 暫時通過，等待實作
+ }
+
+ [Fact]
+ public void TestCase2() {
+ // TODO: 第二個測試案例
+ Assert.True(true);
+ }
+
+ [Fact]
+ public void TestEdgeCases() {
+ // TODO: 邊界情況測試
+ // 空陣列、單一元素、最大值、最小值等
+ Assert.True(true);
+ }
+}
diff --git a/problems/3025-find-the-number-of-ways-to-place-people-i/test/TestProject.csproj b/problems/3025-find-the-number-of-ways-to-place-people-i/test/TestProject.csproj
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+++ b/problems/3025-find-the-number-of-ways-to-place-people-i/test/TestProject.csproj
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+
+
+
+ net8.0
+ enable
+ false
+
+
+
+
+
+
+ runtime; build; native; contentfiles; analyzers; buildtransitive
+ all
+
+
+
+
+
+
+
+
diff --git a/problems/3025-find-the-number-of-ways-to-place-people-i/test/edge_cases.md b/problems/3025-find-the-number-of-ways-to-place-people-i/test/edge_cases.md
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+# 邊界情況清單
+
+## 需要測試的邊界情況
+- [ ] 空輸入 (空陣列、空字串等)
+- [ ] 單一元素
+- [ ] 重複元素
+- [ ] 最大值/最小值
+- [ ] 負數情況
+- [ ] 超大資料量
+- [ ] 特殊字符 (如果是字串題目)
+
+## 額外測試案例
+### 案例 1:
+**輸入**:
+**輸出**:
+**說明**:
+
+### 案例 2:
+**輸入**:
+**輸出**:
+**說明**: