diff --git a/solution/3500-3599/3554.Find Category Recommendation Pairs/README.md b/solution/3500-3599/3554.Find Category Recommendation Pairs/README.md
new file mode 100644
index 0000000000000..4d6311b2874fa
--- /dev/null
+++ b/solution/3500-3599/3554.Find Category Recommendation Pairs/README.md
@@ -0,0 +1,188 @@
+---
+comments: true
+difficulty: 困难
+edit_url: https://github.com/doocs/leetcode/edit/main/solution/3500-3599/3554.Find%20Category%20Recommendation%20Pairs/README.md
+tags:
+ - 数据库
+---
+
+
+
+# [3554. 查找类别推荐对](https://leetcode.cn/problems/find-category-recommendation-pairs)
+
+[English Version](/solution/3500-3599/3554.Find%20Category%20Recommendation%20Pairs/README_EN.md)
+
+## 题目描述
+
+
+
+表：ProductPurchases
+
+
++-------------+------+
+| Column Name | Type |
++-------------+------+
+| user_id | int |
+| product_id | int |
+| quantity | int |
++-------------+------+
+(user_id, product_id) 是这张表的唯一主键。
+每一行代表用户以特定数量购买的一种产品。
+
+
+表：ProductInfo
+
+
++-------------+---------+
+| Column Name | Type |
++-------------+---------+
+| product_id | int |
+| category | varchar |
+| price | decimal |
++-------------+---------+
+product_id 是这张表的唯一主键。
+每一行表示一件商品的类别和价格。
+
+
+亚马逊想要了解不同产品类别的购物模式。编写一个解决方案：
+
+
+ - 查找所有 类别对（其中
category1 < category2）
+ - 对于 每个类别对，确定 同时 购买了两类别产品的 不同用户 数量
+
+
+如果至少有 3 个不同的客户购买了两个类别的产品，则类别对被视为 可报告的。
+
+返回可报告类别对的结果表以 customer_count 降序 排序，并且为了防止排序持平，以 category1 字典序 升序 排序，然后以 category2 升序 排序。
+
+结果格式如下所示。
+
+
+
+示例：
+
+
+
输入：
+
+
ProductPurchases 表：
+
+
++---------+------------+----------+
+| user_id | product_id | quantity |
++---------+------------+----------+
+| 1 | 101 | 2 |
+| 1 | 102 | 1 |
+| 1 | 201 | 3 |
+| 1 | 301 | 1 |
+| 2 | 101 | 1 |
+| 2 | 102 | 2 |
+| 2 | 103 | 1 |
+| 2 | 201 | 5 |
+| 3 | 101 | 2 |
+| 3 | 103 | 1 |
+| 3 | 301 | 4 |
+| 3 | 401 | 2 |
+| 4 | 101 | 1 |
+| 4 | 201 | 3 |
+| 4 | 301 | 1 |
+| 4 | 401 | 2 |
+| 5 | 102 | 2 |
+| 5 | 103 | 1 |
+| 5 | 201 | 2 |
+| 5 | 202 | 3 |
++---------+------------+----------+
+
+
+
ProductInfo 表：
+
+
++------------+-------------+-------+
+| product_id | category | price |
++------------+-------------+-------+
+| 101 | Electronics | 100 |
+| 102 | Books | 20 |
+| 103 | Books | 35 |
+| 201 | Clothing | 45 |
+| 202 | Clothing | 60 |
+| 301 | Sports | 75 |
+| 401 | Kitchen | 50 |
++------------+-------------+-------+
+
+
+
输出：
+
+
++-------------+-------------+----------------+
+| category1 | category2 | customer_count |
++-------------+-------------+----------------+
+| Books | Clothing | 3 |
+| Books | Electronics | 3 |
+| Clothing | Electronics | 3 |
+| Electronics | Sports | 3 |
++-------------+-------------+----------------+
+
+
+
解释：
+
+
+ - Books-Clothing:
+
+
+ - 用户 1 购买来自 Books (102) 和 Clothing (201) 的商品
+ - 用户 2 购买来自 Books (102, 103) 和 Clothing (201) 的商品
+ - 用户 5 购买来自 Books (102, 103) 和 Clothing (201, 202) 的商品
+ - 共计：3 个用户购买同一类别的商品
+
+
+ - Books-Electronics:
+
+ - 用户 1 购买来自 Books (102) 和 Electronics (101) 的商品
+ - 用户 2 购买来自 Books (102, 103) 和 Electronics (101) 的商品
+ - 用户 3 购买来自 Books (103) 和 Electronics (101) 的商品
+ - 共计：3 个消费者购买同一类别的商品
+
+
+ - Clothing-Electronics:
+
+ - 用户 1 购买来自 Clothing (201) 和 Electronics (101) 的商品
+ - 用户 2 购买来自 Clothing (201) 和 Electronics (101) 的商品
+ - 用户 4 购买来自 Clothing (201) 和 Electronics (101) 的商品
+ - 共计：3 个消费者购买同一类别的商品
+
+
+ - Electronics-Sports:
+
+ - 用户 1 购买来自 Electronics (101) 和 Sports (301) 的商品
+ - 用户 3 购买来自 Electronics (101) 和 Sports (301) 的商品
+ - 用户 4 购买来自 Electronics (101) 和 Sports (301) 的商品
+ - 共计：3 个消费者购买同一类别的商品
+
+
+ - 其它类别对比如 Clothing-Sports（只有 2 个消费者：用户 1 和 4）和 Books-Kitchen（只有 1 个消费者：用户 3）共同的消费者少于 3 个，因此不包含在结果内。
+
+
+
+
结果按 customer_count 降序排列。由于所有对都有相同的客户数量 3，它们按 category1（然后是 category2）升序排列。
+
Table: ProductPurchases
+
+
++-------------+------+
+| Column Name | Type |
++-------------+------+
+| user_id | int |
+| product_id | int |
+| quantity | int |
++-------------+------+
+(user_id, product_id) is the unique identifier for this table.
+Each row represents a purchase of a product by a user in a specific quantity.
+
+
+Table: ProductInfo
+
+
++-------------+---------+
+| Column Name | Type |
++-------------+---------+
+| product_id | int |
+| category | varchar |
+| price | decimal |
++-------------+---------+
+product_id is the unique identifier for this table.
+Each row assigns a category and price to a product.
+
+
+Amazon wants to understand shopping patterns across product categories. Write a solution to:
+
+
+ - Find all category pairs (where
category1 < category2)
+ - For each category pair, determine the number of unique customers who purchased products from both categories
+
+
+A category pair is considered reportable if at least 3 different customers have purchased products from both categories.
+
+Return the result table of reportable category pairs ordered by customer_count in descending order, and in case of a tie, by category1 in ascending order lexicographically, and then by category2 in ascending order.
+
+The result format is in the following example.
+
+
+Example:
+
+
+
Input:
+
+
ProductPurchases table:
+
+
++---------+------------+----------+
+| user_id | product_id | quantity |
++---------+------------+----------+
+| 1 | 101 | 2 |
+| 1 | 102 | 1 |
+| 1 | 201 | 3 |
+| 1 | 301 | 1 |
+| 2 | 101 | 1 |
+| 2 | 102 | 2 |
+| 2 | 103 | 1 |
+| 2 | 201 | 5 |
+| 3 | 101 | 2 |
+| 3 | 103 | 1 |
+| 3 | 301 | 4 |
+| 3 | 401 | 2 |
+| 4 | 101 | 1 |
+| 4 | 201 | 3 |
+| 4 | 301 | 1 |
+| 4 | 401 | 2 |
+| 5 | 102 | 2 |
+| 5 | 103 | 1 |
+| 5 | 201 | 2 |
+| 5 | 202 | 3 |
++---------+------------+----------+
+
+
+
ProductInfo table:
+
+
++------------+-------------+-------+
+| product_id | category | price |
++------------+-------------+-------+
+| 101 | Electronics | 100 |
+| 102 | Books | 20 |
+| 103 | Books | 35 |
+| 201 | Clothing | 45 |
+| 202 | Clothing | 60 |
+| 301 | Sports | 75 |
+| 401 | Kitchen | 50 |
++------------+-------------+-------+
+
+
+
Output:
+
+
++-------------+-------------+----------------+
+| category1 | category2 | customer_count |
++-------------+-------------+----------------+
+| Books | Clothing | 3 |
+| Books | Electronics | 3 |
+| Clothing | Electronics | 3 |
+| Electronics | Sports | 3 |
++-------------+-------------+----------------+
+
+
+
Explanation:
+
+
+ - Books-Clothing:
+
+
+ - User 1 purchased products from Books (102) and Clothing (201)
+ - User 2 purchased products from Books (102, 103) and Clothing (201)
+ - User 5 purchased products from Books (102, 103) and Clothing (201, 202)
+ - Total: 3 customers purchased from both categories
+
+
+ - Books-Electronics:
+
+ - User 1 purchased products from Books (102) and Electronics (101)
+ - User 2 purchased products from Books (102, 103) and Electronics (101)
+ - User 3 purchased products from Books (103) and Electronics (101)
+ - Total: 3 customers purchased from both categories
+
+
+ - Clothing-Electronics:
+
+ - User 1 purchased products from Clothing (201) and Electronics (101)
+ - User 2 purchased products from Clothing (201) and Electronics (101)
+ - User 4 purchased products from Clothing (201) and Electronics (101)
+ - Total: 3 customers purchased from both categories
+
+
+ - Electronics-Sports:
+
+ - User 1 purchased products from Electronics (101) and Sports (301)
+ - User 3 purchased products from Electronics (101) and Sports (301)
+ - User 4 purchased products from Electronics (101) and Sports (301)
+ - Total: 3 customers purchased from both categories
+
+
+ - Other category pairs like Clothing-Sports (only 2 customers: Users 1 and 4) and Books-Kitchen (only 1 customer: User 3) have fewer than 3 shared customers and are not included in the result.
+
+
+
+
The result is ordered by customer_count in descending order. Since all pairs have the same customer_count of 3, they are ordered by category1 (then category2) in ascending order.
+
给定一个整数数组 nums 和一个整数 k。
+
+对于每个长度为 k 的连续 子数组，确定必须排序的连续段的最小长度，以便整个窗口成为 非递减 的；如果窗口已经排序，则其所需长度为零。
+
+返回一个长度为 n − k + 1 的数组，其中每个元素对应其窗口的答案。
+
+
+
+示例 1：
+
+
+
输入：nums = [1,3,2,4,5], k = 3
+
+
输出：[2,2,0]
+
+
解释：
+
+
+ nums[0...2] = [1, 3, 2]。排序 [3, 2] 得到 [1, 2, 3]，答案是 2。nums[1...3] = [3, 2, 4]。排序 [3, 2] 得到 [2, 3, 4]，答案是 2。nums[2...4] = [2, 4, 5] 已经有序，所以答案是 0。
+
示例 2：
+
+
+
输入：nums = [5,4,3,2,1], k = 4
+
+
输出：[4,4]
+
+
解释：
+
+
+ nums[0...3] = [5, 4, 3, 2]。整个子数组必须有序，所以答案是4。nums[1...4] = [4, 3, 2, 1]。整个子数组必须有序，所以答案是4。
+
+
+提示：
+
+
+ 1 <= nums.length <= 10001 <= k <= nums.length1 <= nums[i] <= 106
+
+
+
+## 解法
+
+
+
+### 方法一
+
+
+
+#### Python3
+
+```python
+
+```
+
+#### Java
+
+```java
+
+```
+
+#### C++
+
+```cpp
+
+```
+
+#### Go
+
+```go
+
+```
+
+
+
+
+
+
diff --git a/solution/3500-3599/3555.Smallest Subarray to Sort in Every Sliding Window/README_EN.md b/solution/3500-3599/3555.Smallest Subarray to Sort in Every Sliding Window/README_EN.md
new file mode 100644
index 0000000000000..f8a58575d7e24
--- /dev/null
+++ b/solution/3500-3599/3555.Smallest Subarray to Sort in Every Sliding Window/README_EN.md
@@ -0,0 +1,102 @@
+---
+comments: true
+difficulty: Medium
+edit_url: https://github.com/doocs/leetcode/edit/main/solution/3500-3599/3555.Smallest%20Subarray%20to%20Sort%20in%20Every%20Sliding%20Window/README_EN.md
+---
+
+
+
+# [3555. Smallest Subarray to Sort in Every Sliding Window 🔒](https://leetcode.com/problems/smallest-subarray-to-sort-in-every-sliding-window)
+
+[中文文档](/solution/3500-3599/3555.Smallest%20Subarray%20to%20Sort%20in%20Every%20Sliding%20Window/README.md)
+
+## Description
+
+
+
+You are given an integer array nums and an integer k.
+
+For each contiguous subarray of length k, determine the minimum length of a continuous segment that must be sorted so that the entire window becomes non‑decreasing; if the window is already sorted, its required length is zero.
+
+Return an array of length n − k + 1 where each element corresponds to the answer for its window.
+
+
+Example 1:
+
+
+
Input: nums = [1,3,2,4,5], k = 3
+
+
Output: [2,2,0]
+
+
Explanation:
+
+
+ nums[0...2] = [1, 3, 2]. Sort [3, 2] to get [1, 2, 3], the answer is 2.nums[1...3] = [3, 2, 4]. Sort [3, 2] to get [2, 3, 4], the answer is 2.nums[2...4] = [2, 4, 5] is already sorted, so the answer is 0.
+
Example 2:
+
+
+
Input: nums = [5,4,3,2,1], k = 4
+
+
Output: [4,4]
+
+
Explanation:
+
+
+ nums[0...3] = [5, 4, 3, 2]. The whole subarray must be sorted, so the answer is 4.nums[1...4] = [4, 3, 2, 1]. The whole subarray must be sorted, so the answer is 4.
+
+Constraints:
+
+
+ 1 <= nums.length <= 10001 <= k <= nums.length1 <= nums[i] <= 106
+
+
+
+## Solutions
+
+
+
+### Solution 1
+
+
+
+#### Python3
+
+```python
+
+```
+
+#### Java
+
+```java
+
+```
+
+#### C++
+
+```cpp
+
+```
+
+#### Go
+
+```go
+
+```
+
+
+
+
+
+
diff --git a/solution/DATABASE_README.md b/solution/DATABASE_README.md
index 8bb1785a384f2..15667df5e5103 100644
--- a/solution/DATABASE_README.md
+++ b/solution/DATABASE_README.md
@@ -315,6 +315,7 @@
| 3482 | [分析组织层级](/solution/3400-3499/3482.Analyze%20Organization%20Hierarchy/README.md) | `数据库` | 困难 | |
| 3497 | [分析订阅转化](/solution/3400-3499/3497.Analyze%20Subscription%20Conversion/README.md) | `数据库` | 中等 | |
| 3521 | [查找推荐产品对](/solution/3500-3599/3521.Find%20Product%20Recommendation%20Pairs/README.md) | `数据库` | 中等 | |
+| 3554 | [查找类别推荐对](/solution/3500-3599/3554.Find%20Category%20Recommendation%20Pairs/README.md) | `数据库` | 困难 | |
## 版权
diff --git a/solution/DATABASE_README_EN.md b/solution/DATABASE_README_EN.md
index 5ec8e3b4018e1..f8c122fac5ac6 100644
--- a/solution/DATABASE_README_EN.md
+++ b/solution/DATABASE_README_EN.md
@@ -313,6 +313,7 @@ Press Control + F(or Command + F on
| 3482 | [Analyze Organization Hierarchy](/solution/3400-3499/3482.Analyze%20Organization%20Hierarchy/README_EN.md) | `Database` | Hard | |
| 3497 | [Analyze Subscription Conversion](/solution/3400-3499/3497.Analyze%20Subscription%20Conversion/README_EN.md) | `Database` | Medium | |
| 3521 | [Find Product Recommendation Pairs](/solution/3500-3599/3521.Find%20Product%20Recommendation%20Pairs/README_EN.md) | `Database` | Medium | |
+| 3554 | [Find Category Recommendation Pairs](/solution/3500-3599/3554.Find%20Category%20Recommendation%20Pairs/README_EN.md) | `Database` | Hard | |
## Copyright
diff --git a/solution/README.md b/solution/README.md
index d37296a5fde6e..3baeaa53c3b82 100644
--- a/solution/README.md
+++ b/solution/README.md
@@ -3564,6 +3564,8 @@
| 3551 | [数位和排序需要的最小交换次数](/solution/3500-3599/3551.Minimum%20Swaps%20to%20Sort%20by%20Digit%20Sum/README.md) | | 中等 | 第 450 场周赛 |
| 3552 | [网格传送门旅游](/solution/3500-3599/3552.Grid%20Teleportation%20Traversal/README.md) | | 中等 | 第 450 场周赛 |
| 3553 | [包含给定路径的最小带权子树 II](/solution/3500-3599/3553.Minimum%20Weighted%20Subgraph%20With%20the%20Required%20Paths%20II/README.md) | | 困难 | 第 450 场周赛 |
+| 3554 | [查找类别推荐对](/solution/3500-3599/3554.Find%20Category%20Recommendation%20Pairs/README.md) | `数据库` | 困难 | |
+| 3555 | [排序每个滑动窗口中最小的子数组](/solution/3500-3599/3555.Smallest%20Subarray%20to%20Sort%20in%20Every%20Sliding%20Window/README.md) | | 中等 | 🔒 |
## 版权
diff --git a/solution/README_EN.md b/solution/README_EN.md
index 3b8936cbd58ac..44f18b19ee47a 100644
--- a/solution/README_EN.md
+++ b/solution/README_EN.md
@@ -3562,6 +3562,8 @@ Press Control + F(or Command + F on
| 3551 | [Minimum Swaps to Sort by Digit Sum](/solution/3500-3599/3551.Minimum%20Swaps%20to%20Sort%20by%20Digit%20Sum/README_EN.md) | | Medium | Weekly Contest 450 |
| 3552 | [Grid Teleportation Traversal](/solution/3500-3599/3552.Grid%20Teleportation%20Traversal/README_EN.md) | | Medium | Weekly Contest 450 |
| 3553 | [Minimum Weighted Subgraph With the Required Paths II](/solution/3500-3599/3553.Minimum%20Weighted%20Subgraph%20With%20the%20Required%20Paths%20II/README_EN.md) | | Hard | Weekly Contest 450 |
+| 3554 | [Find Category Recommendation Pairs](/solution/3500-3599/3554.Find%20Category%20Recommendation%20Pairs/README_EN.md) | `Database` | Hard | |
+| 3555 | [Smallest Subarray to Sort in Every Sliding Window](/solution/3500-3599/3555.Smallest%20Subarray%20to%20Sort%20in%20Every%20Sliding%20Window/README_EN.md) | | Medium | 🔒 |
## Copyright