Merge pull request #732 from openset/develop

Add: new

README.md

@@ -62,6 +62,11 @@ LeetCode Problems' Solutions
 
 | # | Title | Solution | Difficulty |
 | :-: | - | - | :-: |
+| <span id="1284">1284</span> | [Minimum Number of Flips to Convert Binary Matrix to Zero Matrix](https://leetcode.com/problems/minimum-number-of-flips-to-convert-binary-matrix-to-zero-matrix "转化为全零矩阵的最少反转次数") | [Go](https://github.com/openset/leetcode/tree/master/problems/minimum-number-of-flips-to-convert-binary-matrix-to-zero-matrix) | Hard |
+| <span id="1283">1283</span> | [Find the Smallest Divisor Given a Threshold](https://leetcode.com/problems/find-the-smallest-divisor-given-a-threshold "使结果不超过阈值的最小除数") | [Go](https://github.com/openset/leetcode/tree/master/problems/find-the-smallest-divisor-given-a-threshold) | Medium |
+| <span id="1282">1282</span> | [Group the People Given the Group Size They Belong To](https://leetcode.com/problems/group-the-people-given-the-group-size-they-belong-to "用户分组") | [Go](https://github.com/openset/leetcode/tree/master/problems/group-the-people-given-the-group-size-they-belong-to) | Medium |
+| <span id="1281">1281</span> | [Subtract the Product and Sum of Digits of an Integer](https://leetcode.com/problems/subtract-the-product-and-sum-of-digits-of-an-integer "整数的各位积和之差") | [Go](https://github.com/openset/leetcode/tree/master/problems/subtract-the-product-and-sum-of-digits-of-an-integer) | Easy |
+| <span id="1280">1280</span> | [Students and Examinations](https://leetcode.com/problems/students-and-examinations) 🔒 | [MySQL](https://github.com/openset/leetcode/tree/master/problems/students-and-examinations) | Easy |
 | <span id="1279">1279</span> | [Traffic Light Controlled Intersection](https://leetcode.com/problems/traffic-light-controlled-intersection) 🔒 | [Go](https://github.com/openset/leetcode/tree/master/problems/traffic-light-controlled-intersection) | Easy |
 | <span id="1278">1278</span> | [Palindrome Partitioning III](https://leetcode.com/problems/palindrome-partitioning-iii "分割回文串 III") | [Go](https://github.com/openset/leetcode/tree/master/problems/palindrome-partitioning-iii) | Hard |
 | <span id="1277">1277</span> | [Count Square Submatrices with All Ones](https://leetcode.com/problems/count-square-submatrices-with-all-ones "统计全为 1 的正方形子矩阵") | [Go](https://github.com/openset/leetcode/tree/master/problems/count-square-submatrices-with-all-ones) | Medium |

internal/leetcode/question_translation.go

@@ -17,12 +17,7 @@ type qtDataType struct {
 }
 
 type translationsType struct {
-	Title    string         `json:"title"`
-	Question questionIDType `json:"question"`
-	TypeName string         `json:"__typename"`
-}
-
-type questionIDType struct {
+	Title      string `json:"title"`
 	QuestionID string `json:"questionId"`
 	TypeName   string `json:"__typename"`
 }
@@ -32,7 +27,7 @@ func GetQuestionTranslation() (qt QuestionTranslationType) {
 	jsonStr := `{
 		"operationName": "getQuestionTranslation",
 		"variables": {},
-		"query": "query getQuestionTranslation($lang: String) {\n  translations: allAppliedQuestionTranslations(lang: $lang) {\n    title\n    question {\n      questionId\n      __typename\n    }\n    __typename\n  }\n}\n"
+		"query": "query getQuestionTranslation($lang: String) {\n  translations: allAppliedQuestionTranslations(lang: $lang) {\n    title\n    questionId\n    __typename\n  }\n}\n"
 	}`
 	graphQLRequest(graphQLCnURL, jsonStr, questionTranslationFile, 2, &qt)
 	if qt.Data.Translations == nil {
@@ -47,7 +42,7 @@ func GetQuestionTranslation() (qt QuestionTranslationType) {
 func init() {
 	translation := GetQuestionTranslation()
 	for _, item := range translation.Data.Translations {
-		id := item.Question.QuestionID
+		id := item.QuestionID
 		if id, err := strconv.Atoi(id); err == nil {
 			translationSet[id] = item.Title
 		}

problems/find-the-smallest-divisor-given-a-threshold/README.md

@@ -0,0 +1,65 @@
+<!--|This file generated by command(leetcode description); DO NOT EDIT.    |-->
+<!--+----------------------------------------------------------------------+-->
+<!--|@author    openset <openset.wang@gmail.com>                           |-->
+<!--|@link      https://github.com/openset                                 |-->
+<!--|@home      https://github.com/openset/leetcode                        |-->
+<!--+----------------------------------------------------------------------+-->
+
+[< Previous](https://github.com/openset/leetcode/tree/master/problems/group-the-people-given-the-group-size-they-belong-to "Group the People Given the Group Size They Belong To")
+
+[Next >](https://github.com/openset/leetcode/tree/master/problems/minimum-number-of-flips-to-convert-binary-matrix-to-zero-matrix "Minimum Number of Flips to Convert Binary Matrix to Zero Matrix")
+
+## [1283. Find the Smallest Divisor Given a Threshold (Medium)](https://leetcode.com/problems/find-the-smallest-divisor-given-a-threshold "使结果不超过阈值的最小除数")
+
+<p>Given an array of integers <code>nums</code> and an integer <code>threshold</code>, we will choose a positive integer divisor and&nbsp;divide&nbsp;all the array by it and sum the result of the division. Find the <strong>smallest</strong> divisor such that the result mentioned above is less than&nbsp;or equal to <code>threshold</code>.</p>
+
+<p>Each&nbsp;result of&nbsp;division is rounded&nbsp;to the nearest integer greater than or equal to that element.&nbsp;(For example: 7/3 = 3 and 10/2 = 5).</p>
+
+<p>It is guaranteed that there will be an answer.</p>
+
+<p>&nbsp;</p>
+<p><strong>Example 1:</strong></p>
+
+<pre>
+<strong>Input:</strong> nums = [1,2,5,9], threshold = 6
+<strong>Output:</strong> 5
+<strong>Explanation:</strong> We can get a sum to 17 (1+2+5+9) if the divisor is 1. 
+If the divisor is 4 we can get a sum to 7 (1+1+2+3) and if the divisor is 5 the sum will be 5 (1+1+1+2). 
+</pre>
+
+<p><strong>Example 2:</strong></p>
+
+<pre>
+<strong>Input:</strong> nums = [2,3,5,7,11], threshold = 11
+<strong>Output:</strong> 3
+</pre>
+
+<p><strong>Example 3:</strong></p>
+
+<pre>
+<strong>Input:</strong> nums = [19], threshold = 5
+<strong>Output:</strong> 4
+</pre>
+
+<p>&nbsp;</p>
+<p><strong>Constraints:</strong></p>
+
+<ul>
+	<li><code>1 &lt;= nums.length &lt;= 5 * 10^4</code></li>
+	<li><code>1 &lt;= nums[i] &lt;= 10^6</code></li>
+	<li><code>nums.length &lt;=&nbsp;threshold &lt;= 10^6</code></li>
+</ul>
+
+### Related Topics
+  [[Binary Search](https://github.com/openset/leetcode/tree/master/tag/binary-search/README.md)]
+
+### Hints
+<details>
+<summary>Hint 1</summary>
+Examine every possible number for solution. Choose the largest of them.
+</details>
+
+<details>
+<summary>Hint 2</summary>
+Use binary search to reduce the time complexity.
+</details>

problems/group-the-people-given-the-group-size-they-belong-to/README.md

@@ -0,0 +1,56 @@
+<!--|This file generated by command(leetcode description); DO NOT EDIT.    |-->
+<!--+----------------------------------------------------------------------+-->
+<!--|@author    openset <openset.wang@gmail.com>                           |-->
+<!--|@link      https://github.com/openset                                 |-->
+<!--|@home      https://github.com/openset/leetcode                        |-->
+<!--+----------------------------------------------------------------------+-->
+
+[< Previous](https://github.com/openset/leetcode/tree/master/problems/subtract-the-product-and-sum-of-digits-of-an-integer "Subtract the Product and Sum of Digits of an Integer")
+
+[Next >](https://github.com/openset/leetcode/tree/master/problems/find-the-smallest-divisor-given-a-threshold "Find the Smallest Divisor Given a Threshold")
+
+## [1282. Group the People Given the Group Size They Belong To (Medium)](https://leetcode.com/problems/group-the-people-given-the-group-size-they-belong-to "用户分组")
+
+<p>There are <code>n</code> people whose <strong>IDs</strong> go from <code>0</code> to <code>n - 1</code> and each person belongs <strong>exactly</strong> to one&nbsp;group. Given the array&nbsp;<code>groupSizes</code> of length <code>n</code> telling the group size each person belongs to, return the groups there are and the people&#39;s&nbsp;<strong>IDs</strong> each group includes.</p>
+
+<p>You can return any solution in any order and the same applies for IDs. Also, it is guaranteed that there exists at least one solution.&nbsp;</p>
+
+<p>&nbsp;</p>
+<p><strong>Example 1:</strong></p>
+
+<pre>
+<strong>Input:</strong> groupSizes = [3,3,3,3,3,1,3]
+<strong>Output:</strong> [[5],[0,1,2],[3,4,6]]
+<b>Explanation:</b> 
+Other possible solutions are [[2,1,6],[5],[0,4,3]] and [[5],[0,6,2],[4,3,1]].
+</pre>
+
+<p><strong>Example 2:</strong></p>
+
+<pre>
+<strong>Input:</strong> groupSizes = [2,1,3,3,3,2]
+<strong>Output:</strong> [[1],[0,5],[2,3,4]]
+</pre>
+
+<p>&nbsp;</p>
+<p><strong>Constraints:</strong></p>
+
+<ul>
+	<li><code>groupSizes.length == n</code></li>
+	<li><code>1 &lt;= n&nbsp;&lt;= 500</code></li>
+	<li><code>1 &lt;=&nbsp;groupSizes[i] &lt;= n</code></li>
+</ul>
+
+### Related Topics
+  [[Greedy](https://github.com/openset/leetcode/tree/master/tag/greedy/README.md)]
+
+### Hints
+<details>
+<summary>Hint 1</summary>
+Put people's IDs with same groupSize into buckets, then split each bucket into groups.
+</details>
+
+<details>
+<summary>Hint 2</summary>
+Greedy fill until you need a new group.
+</details>

problems/minimum-number-of-flips-to-convert-binary-matrix-to-zero-matrix/README.md

@@ -0,0 +1,72 @@
+<!--|This file generated by command(leetcode description); DO NOT EDIT.    |-->
+<!--+----------------------------------------------------------------------+-->
+<!--|@author    openset <openset.wang@gmail.com>                           |-->
+<!--|@link      https://github.com/openset                                 |-->
+<!--|@home      https://github.com/openset/leetcode                        |-->
+<!--+----------------------------------------------------------------------+-->
+
+[< Previous](https://github.com/openset/leetcode/tree/master/problems/find-the-smallest-divisor-given-a-threshold "Find the Smallest Divisor Given a Threshold")
+
+Next >
+
+## [1284. Minimum Number of Flips to Convert Binary Matrix to Zero Matrix (Hard)](https://leetcode.com/problems/minimum-number-of-flips-to-convert-binary-matrix-to-zero-matrix "转化为全零矩阵的最少反转次数")
+
+<p>Given a <code>m x n</code> binary matrix <code>mat</code>. In one step, you can choose one cell and flip it and all the four neighbours of it&nbsp;if they exist (Flip is changing 1 to 0 and 0 to 1). A pair of cells are called neighboors if they share one edge.</p>
+
+<p>Return the <em>minimum number of steps</em> required to convert <code>mat</code>&nbsp;to a zero matrix or <strong>-1</strong> if you cannot.</p>
+
+<p>Binary matrix is a matrix with all cells equal to 0 or 1 only.</p>
+
+<p>Zero matrix is a matrix with all cells equal to 0.</p>
+
+<p>&nbsp;</p>
+<p><strong>Example 1:</strong></p>
+<img alt="" src="https://assets.leetcode.com/uploads/2019/11/28/matrix.png" style="width: 409px; height: 86px;" />
+<pre>
+<strong>Input:</strong> mat = [[0,0],[0,1]]
+<strong>Output:</strong> 3
+<strong>Explanation:</strong> One possible solution is to flip (1, 0) then (0, 1) and finally (1, 1) as shown.
+</pre>
+
+<p><strong>Example 2:</strong></p>
+
+<pre>
+<strong>Input:</strong> mat = [[0]]
+<strong>Output:</strong> 0
+<strong>Explanation:</strong> Given matrix is a zero matrix. We don&#39;t need to change it.
+</pre>
+
+<p><strong>Example 3:</strong></p>
+
+<pre>
+<strong>Input:</strong> mat = [[1,1,1],[1,0,1],[0,0,0]]
+<strong>Output:</strong> 6
+</pre>
+
+<p><strong>Example 4:</strong></p>
+
+<pre>
+<strong>Input:</strong> mat = [[1,0,0],[1,0,0]]
+<strong>Output:</strong> -1
+<strong>Explanation:</strong> Given matrix can&#39;t be a zero matrix
+</pre>
+
+<p>&nbsp;</p>
+<p><strong>Constraints:</strong></p>
+
+<ul>
+	<li><code>m ==&nbsp;mat.length</code></li>
+	<li><code>n ==&nbsp;mat[0].length</code></li>
+	<li><code>1 &lt;= m&nbsp;&lt;= 3</code></li>
+	<li><code>1 &lt;= n&nbsp;&lt;= 3</code></li>
+	<li><code>mat[i][j]</code> is 0 or 1.</li>
+</ul>
+
+### Related Topics
+  [[Breadth-first Search](https://github.com/openset/leetcode/tree/master/tag/breadth-first-search/README.md)]
+
+### Hints
+<details>
+<summary>Hint 1</summary>
+Flipping same index two times is like not flipping it at all. Each index can be flipped one time. Try all possible combinations. O(2^(n*m)).
+</details>

problems/students-and-examinations/README.md

@@ -0,0 +1,111 @@
+<!--|This file generated by command(leetcode description); DO NOT EDIT.    |-->
+<!--+----------------------------------------------------------------------+-->
+<!--|@author    openset <openset.wang@gmail.com>                           |-->
+<!--|@link      https://github.com/openset                                 |-->
+<!--|@home      https://github.com/openset/leetcode                        |-->
+<!--+----------------------------------------------------------------------+-->
+
+[< Previous](https://github.com/openset/leetcode/tree/master/problems/traffic-light-controlled-intersection "Traffic Light Controlled Intersection")
+
+[Next >](https://github.com/openset/leetcode/tree/master/problems/subtract-the-product-and-sum-of-digits-of-an-integer "Subtract the Product and Sum of Digits of an Integer")
+
+## [1280. Students and Examinations (Easy)](https://leetcode.com/problems/students-and-examinations "")
+
+<p>Table: <code>Students</code></p>
+<pre>
++---------------+---------+
+| Column Name   | Type    |
++---------------+---------+
+| student_id    | int     |
+| student_name  | varchar |
++---------------+---------+
+student_id is the primary key for this table.
+Each row of this table contains the ID and the name of one student in the school.
+</pre>
+
+<p>Table: <code>Subjects</code></p>
+<pre>
++--------------+---------+
+| Column Name  | Type    |
++--------------+---------+
+| subject_name | varchar |
++--------------+---------+
+subject_name is the primary key for this table.
+Each row of this table contains a name of one subject in the school.
+</pre>
+
+<p>Table: <code>Examinations</code></p>
+<pre>
++--------------+---------+
+| Column Name  | Type    |
++--------------+---------+
+| student_id   | int     |
+| subject_name | varchar |
++--------------+---------+
+There is no primary key for this table. It may contain duplicates.
+Each student from Students table takes every course from Subjects table.
+Each row of this table indicates that a student with ID student_id attended the exam of subject_name.
+</pre>
+
+Write an SQL query to find the number of times each student attended each exam.
+
+Order the result table by student_id and subject_name.
+
+The query result format is in the following example:
+<pre>
+Students table:
++------------+--------------+
+| student_id | student_name |
++------------+--------------+
+| 1          | Alice        |
+| 2          | Bob          |
+| 13         | John         |
+| 6          | Alex         |
++------------+--------------+
+Subjects table:
++--------------+
+| subject_name |
++--------------+
+| Math         |
+| Physics      |
+| Programming  |
++--------------+
+Examinations table:
++------------+--------------+
+| student_id | subject_name |
++------------+--------------+
+| 1          | Math         |
+| 1          | Physics      |
+| 1          | Programming  |
+| 2          | Programming  |
+| 1          | Physics      |
+| 1          | Math         |
+| 13         | Math         |
+| 13         | Programming  |
+| 13         | Physics      |
+| 2          | Math         |
+| 1          | Math         |
++------------+--------------+
+Result table:
++------------+--------------+--------------+----------------+
+| student_id | student_name | subject_name | attended_exams |
++------------+--------------+--------------+----------------+
+| 1          | Alice        | Math         | 3              |
+| 1          | Alice        | Physics      | 2              |
+| 1          | Alice        | Programming  | 1              |
+| 2          | Bob          | Math         | 1              |
+| 2          | Bob          | Physics      | 0              |
+| 2          | Bob          | Programming  | 1              |
+| 6          | Alex         | Math         | 0              |
+| 6          | Alex         | Physics      | 0              |
+| 6          | Alex         | Programming  | 0              |
+| 13         | John         | Math         | 1              |
+| 13         | John         | Physics      | 1              |
+| 13         | John         | Programming  | 1              |
++------------+--------------+--------------+----------------+
+The result table should contain all students and all subjects.
+Alice attended Math exam 3 times, Physics exam 2 times and Programming exam 1 time.
+Bob attended Math exam 1 time, Programming exam 1 time and didn't attend the Physics exam.
+Alex didn't attend any exam.
+John attended Math exam 1 time, Physics exam 1 time and Programming exam 1 time.
+</pre>

problems/students-and-examinations/mysql_schemas.sql

@@ -0,0 +1,24 @@
+Create table If Not Exists Students (student_id int, student_name varchar(20));
+Create table If Not Exists Subjects (subject_name varchar(20));
+Create table If Not Exists Examinations (student_id int, subject_name varchar(20));
+Truncate table Students;
+insert into Students (student_id, student_name) values ('1', 'Alice');
+insert into Students (student_id, student_name) values ('2', 'Bob');
+insert into Students (student_id, student_name) values ('13', 'John');
+insert into Students (student_id, student_name) values ('6', 'Alex');
+Truncate table Subjects;
+insert into Subjects (subject_name) values ('Math');
+insert into Subjects (subject_name) values ('Physics');
+insert into Subjects (subject_name) values ('Programming');
+Truncate table Examinations;
+insert into Examinations (student_id, subject_name) values ('1', 'Math');
+insert into Examinations (student_id, subject_name) values ('1', 'Physics');
+insert into Examinations (student_id, subject_name) values ('1', 'Programming');
+insert into Examinations (student_id, subject_name) values ('2', 'Programming');
+insert into Examinations (student_id, subject_name) values ('1', 'Physics');
+insert into Examinations (student_id, subject_name) values ('1', 'Math');
+insert into Examinations (student_id, subject_name) values ('13', 'Math');
+insert into Examinations (student_id, subject_name) values ('13', 'Programming');
+insert into Examinations (student_id, subject_name) values ('13', 'Physics');
+insert into Examinations (student_id, subject_name) values ('2', 'Math');
+insert into Examinations (student_id, subject_name) values ('1', 'Math');