Add: new

openset · openset · commit 1f7d2b94d6b9 · 2019-07-16T09:48:18.000+08:00
diff --git a/README.md b/README.md
@@ -54,10 +54,19 @@ LeetCode Problems' Solutions
 
 | # | Title | Solution | Difficulty |
 | :-: | - | - | :-: |
-| <span id="1117">1117</span> | [Building H2O](https://leetcode.com/problems/building-h2o) | [Go](https://github.com/openset/leetcode/tree/master/problems/building-h2o) | Hard |
+| <span id="1126">1126</span> | [Active Businesses](https://leetcode.com/problems/active-businesses) 🔒 | [MySQL](https://github.com/openset/leetcode/tree/master/problems/active-businesses) | Medium |
+| <span id="1125">1125</span> | [Smallest Sufficient Team](https://leetcode.com/problems/smallest-sufficient-team "最小的必要团队") | [Go](https://github.com/openset/leetcode/tree/master/problems/smallest-sufficient-team) | Hard |
+| <span id="1124">1124</span> | [Longest Well-Performing Interval](https://leetcode.com/problems/longest-well-performing-interval "表现良好的最长时间段") | [Go](https://github.com/openset/leetcode/tree/master/problems/longest-well-performing-interval) | Medium |
+| <span id="1123">1123</span> | [Lowest Common Ancestor of Deepest Leaves](https://leetcode.com/problems/lowest-common-ancestor-of-deepest-leaves "最深叶节点的最近公共祖先") | [Go](https://github.com/openset/leetcode/tree/master/problems/lowest-common-ancestor-of-deepest-leaves) | Medium |
+| <span id="1122">1122</span> | [Relative Sort Array](https://leetcode.com/problems/relative-sort-array "数组的相对排序") | [Go](https://github.com/openset/leetcode/tree/master/problems/relative-sort-array) | Easy |
+| <span id="1121">1121</span> | [Divide Array Into Increasing Sequences](https://leetcode.com/problems/divide-array-into-increasing-sequences "将数组分成几个递增序列") 🔒 | [Go](https://github.com/openset/leetcode/tree/master/problems/divide-array-into-increasing-sequences) | Hard |
+| <span id="1120">1120</span> | [Maximum Average Subtree](https://leetcode.com/problems/maximum-average-subtree "子树的最大平均值") 🔒 | [Go](https://github.com/openset/leetcode/tree/master/problems/maximum-average-subtree) | Medium |
+| <span id="1119">1119</span> | [Remove Vowels from a String](https://leetcode.com/problems/remove-vowels-from-a-string "删去字符串中的元音") 🔒 | [Go](https://github.com/openset/leetcode/tree/master/problems/remove-vowels-from-a-string) | Easy |
+| <span id="1118">1118</span> | [Number of Days in a Month](https://leetcode.com/problems/number-of-days-in-a-month "一月有多少天") 🔒 | [Go](https://github.com/openset/leetcode/tree/master/problems/number-of-days-in-a-month) | Easy |
+| <span id="1117">1117</span> | [Building H2O](https://leetcode.com/problems/building-h2o "H2O 生成") | [Go](https://github.com/openset/leetcode/tree/master/problems/building-h2o) | Hard |
 | <span id="1116">1116</span> | [Print Zero Even Odd](https://leetcode.com/problems/print-zero-even-odd) | [Go](https://github.com/openset/leetcode/tree/master/problems/print-zero-even-odd) | Medium |
 | <span id="1115">1115</span> | [Print FooBar Alternately](https://leetcode.com/problems/print-foobar-alternately) | [Go](https://github.com/openset/leetcode/tree/master/problems/print-foobar-alternately) | Medium |
-| <span id="1114">1114</span> | [Print in Order](https://leetcode.com/problems/print-in-order) | [Go](https://github.com/openset/leetcode/tree/master/problems/print-in-order) | Easy |
+| <span id="1114">1114</span> | [Print in Order](https://leetcode.com/problems/print-in-order "按序打印") | [Go](https://github.com/openset/leetcode/tree/master/problems/print-in-order) | Easy |
 | <span id="1113">1113</span> | [Reported Posts](https://leetcode.com/problems/reported-posts) 🔒 | [MySQL](https://github.com/openset/leetcode/tree/master/problems/reported-posts) | Easy |
 | <span id="1112">1112</span> | [Highest Grade For Each Student](https://leetcode.com/problems/highest-grade-for-each-student) 🔒 | [MySQL](https://github.com/openset/leetcode/tree/master/problems/highest-grade-for-each-student) | Medium |
 | <span id="1111">1111</span> | [Maximum Nesting Depth of Two Valid Parentheses Strings](https://leetcode.com/problems/maximum-nesting-depth-of-two-valid-parentheses-strings "有效括号的嵌套深度") | [Go](https://github.com/openset/leetcode/tree/master/problems/maximum-nesting-depth-of-two-valid-parentheses-strings) | Medium |
diff --git a/problems/active-businesses/README.md b/problems/active-businesses/README.md
@@ -0,0 +1,14 @@
+<!--|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/smallest-sufficient-team "Smallest Sufficient Team")
+　　　　　　　　　　　　　　　　
+Next >
+
+## 1126. Active Businesses (Medium)
+
+
diff --git a/problems/active-businesses/mysql_schemas.sql b/problems/active-businesses/mysql_schemas.sql
@@ -0,0 +1,9 @@
+Create table If Not Exists Events (business_id int, event_type varchar(10), occurences int);
+Truncate table Events;
+insert into Events (business_id, event_type, occurences) values ('1', 'reviews', '7');
+insert into Events (business_id, event_type, occurences) values ('3', 'reviews', '3');
+insert into Events (business_id, event_type, occurences) values ('1', 'ads', '11');
+insert into Events (business_id, event_type, occurences) values ('2', 'ads', '7');
+insert into Events (business_id, event_type, occurences) values ('3', 'ads', '6');
+insert into Events (business_id, event_type, occurences) values ('1', 'page views', '3');
+insert into Events (business_id, event_type, occurences) values ('2', 'page views', '12');
diff --git a/problems/best-time-to-buy-and-sell-stock-ii/README.md b/problems/best-time-to-buy-and-sell-stock-ii/README.md
@@ -44,8 +44,8 @@
 <strong>Explanation:</strong> In this case, no transaction is done, i.e. max profit = 0.</pre>
 
 ### Related Topics
-  [[Greedy](https://github.com/openset/leetcode/tree/master/tag/greedy/README.md)]
   [[Array](https://github.com/openset/leetcode/tree/master/tag/array/README.md)]
+  [[Greedy](https://github.com/openset/leetcode/tree/master/tag/greedy/README.md)]
 
 ### Similar Questions
   1. [Best Time to Buy and Sell Stock](https://github.com/openset/leetcode/tree/master/problems/best-time-to-buy-and-sell-stock) (Easy)
diff --git a/problems/binary-tree-inorder-traversal/README.md b/problems/binary-tree-inorder-traversal/README.md
@@ -28,9 +28,9 @@
 <p><strong>Follow up:</strong> Recursive solution is trivial, could you do it iteratively?</p>
 
 ### Related Topics
+  [[Hash Table](https://github.com/openset/leetcode/tree/master/tag/hash-table/README.md)]
   [[Stack](https://github.com/openset/leetcode/tree/master/tag/stack/README.md)]
   [[Tree](https://github.com/openset/leetcode/tree/master/tag/tree/README.md)]
-  [[Hash Table](https://github.com/openset/leetcode/tree/master/tag/hash-table/README.md)]
 
 ### Similar Questions
   1. [Validate Binary Search Tree](https://github.com/openset/leetcode/tree/master/problems/validate-binary-search-tree) (Medium)
diff --git a/problems/building-h2o/README.md b/problems/building-h2o/README.md
@@ -7,7 +7,7 @@
 
 [< Previous](https://github.com/openset/leetcode/tree/master/problems/print-zero-even-odd "Print Zero Even Odd")
 　　　　　　　　　　　　　　　　
-Next >
+[Next >](https://github.com/openset/leetcode/tree/master/problems/number-of-days-in-a-month "Number of Days in a Month")
 
 ## 1117. Building H2O (Hard)
 
diff --git a/problems/construct-binary-tree-from-inorder-and-postorder-traversal/README.md b/problems/construct-binary-tree-from-inorder-and-postorder-traversal/README.md
@@ -33,9 +33,9 @@ postorder = [9,15,7,20,3]</pre>
 </pre>
 
 ### Related Topics
+  [[Array](https://github.com/openset/leetcode/tree/master/tag/array/README.md)]
   [[Tree](https://github.com/openset/leetcode/tree/master/tag/tree/README.md)]
   [[Depth-first Search](https://github.com/openset/leetcode/tree/master/tag/depth-first-search/README.md)]
-  [[Array](https://github.com/openset/leetcode/tree/master/tag/array/README.md)]
 
 ### Similar Questions
   1. [Construct Binary Tree from Preorder and Inorder Traversal](https://github.com/openset/leetcode/tree/master/problems/construct-binary-tree-from-preorder-and-inorder-traversal) (Medium)
diff --git a/problems/construct-binary-tree-from-preorder-and-inorder-traversal/README.md b/problems/construct-binary-tree-from-preorder-and-inorder-traversal/README.md
@@ -32,9 +32,9 @@ inorder = [9,3,15,20,7]</pre>
    15   7</pre>
 
 ### Related Topics
+  [[Array](https://github.com/openset/leetcode/tree/master/tag/array/README.md)]
   [[Tree](https://github.com/openset/leetcode/tree/master/tag/tree/README.md)]
   [[Depth-first Search](https://github.com/openset/leetcode/tree/master/tag/depth-first-search/README.md)]
-  [[Array](https://github.com/openset/leetcode/tree/master/tag/array/README.md)]
 
 ### Similar Questions
   1. [Construct Binary Tree from Inorder and Postorder Traversal](https://github.com/openset/leetcode/tree/master/problems/construct-binary-tree-from-inorder-and-postorder-traversal) (Medium)
diff --git a/problems/convert-sorted-list-to-binary-search-tree/README.md b/problems/convert-sorted-list-to-binary-search-tree/README.md
@@ -30,8 +30,8 @@ One possible answer is: [0,-3,9,-10,null,5], which represents the following heig
 </pre>
 
 ### Related Topics
-  [[Depth-first Search](https://github.com/openset/leetcode/tree/master/tag/depth-first-search/README.md)]
   [[Linked List](https://github.com/openset/leetcode/tree/master/tag/linked-list/README.md)]
+  [[Depth-first Search](https://github.com/openset/leetcode/tree/master/tag/depth-first-search/README.md)]
 
 ### Similar Questions
   1. [Convert Sorted Array to Binary Search Tree](https://github.com/openset/leetcode/tree/master/problems/convert-sorted-array-to-binary-search-tree) (Easy)
diff --git a/problems/divide-array-into-increasing-sequences/README.md b/problems/divide-array-into-increasing-sequences/README.md
@@ -0,0 +1,43 @@
+<!--|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/maximum-average-subtree "Maximum Average Subtree")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/relative-sort-array "Relative Sort Array")
+
+## 1121. Divide Array Into Increasing Sequences (Hard)
+
+
+
+### Related Topics
+  [[Math](https://github.com/openset/leetcode/tree/master/tag/math/README.md)]
+
+### Hints
+<details>
+<summary>Hint 1</summary>
+Think in the frequency of the numbers and how this affects the number of sequences needed.
+</details>
+
+<details>
+<summary>Hint 2</summary>
+What is the minimum number of sequences we need to form? Considering frequency of the numbers.
+</details>
+
+<details>
+<summary>Hint 3</summary>
+Think about the least number of sequences to maximize the lengths.
+</details>
+
+<details>
+<summary>Hint 4</summary>
+The number of sequences needed is equal to the maximum frequency of an element.
+</details>
+
+<details>
+<summary>Hint 5</summary>
+How to put the other elements into sequences ? Think in a greedy approach.
+</details>
diff --git a/problems/largest-rectangle-in-histogram/README.md b/problems/largest-rectangle-in-histogram/README.md
@@ -33,8 +33,8 @@
 </pre>
 
 ### Related Topics
-  [[Stack](https://github.com/openset/leetcode/tree/master/tag/stack/README.md)]
   [[Array](https://github.com/openset/leetcode/tree/master/tag/array/README.md)]
+  [[Stack](https://github.com/openset/leetcode/tree/master/tag/stack/README.md)]
 
 ### Similar Questions
   1. [Maximal Rectangle](https://github.com/openset/leetcode/tree/master/problems/maximal-rectangle) (Hard)
diff --git a/problems/longest-well-performing-interval/README.md b/problems/longest-well-performing-interval/README.md
@@ -0,0 +1,39 @@
+<!--|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/lowest-common-ancestor-of-deepest-leaves "Lowest Common Ancestor of Deepest Leaves")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/smallest-sufficient-team "Smallest Sufficient Team")
+
+## 1124. Longest Well-Performing Interval (Medium)
+
+<p>We are given <code>hours</code>, a list of the number of hours&nbsp;worked per day for a given employee.</p>
+
+<p>A day is considered to be a <em>tiring day</em> if and only if the number of hours worked is (strictly) greater than <code>8</code>.</p>
+
+<p>A <em>well-performing interval</em> is an interval of days for which the number of tiring days is strictly larger than the number of non-tiring days.</p>
+
+<p>Return the length of the longest well-performing interval.</p>
+
+<p>&nbsp;</p>
+<p><strong>Example 1:</strong></p>
+
+<pre>
+<strong>Input:</strong> hours = [9,9,6,0,6,6,9]
+<strong>Output:</strong> 3
+<strong>Explanation: </strong>The longest well-performing interval is [9,9,6].<button type="default"></button></pre>
+
+<p>&nbsp;</p>
+<p><strong>Constraints:</strong></p>
+
+<ul>
+	<li><code>1 &lt;= hours.length &lt;= 10000</code></li>
+	<li><code>0 &lt;= hours[i] &lt;= 16</code></li>
+</ul>
+
+### Related Topics
+  [[Stack](https://github.com/openset/leetcode/tree/master/tag/stack/README.md)]
diff --git a/problems/lowest-common-ancestor-of-deepest-leaves/README.md b/problems/lowest-common-ancestor-of-deepest-leaves/README.md
@@ -0,0 +1,60 @@
+<!--|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/relative-sort-array "Relative Sort Array")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/longest-well-performing-interval "Longest Well-Performing Interval")
+
+## 1123. Lowest Common Ancestor of Deepest Leaves (Medium)
+
+<p>Given a rooted binary tree, return the lowest common ancestor of its deepest leaves.</p>
+
+<p>Recall that:</p>
+
+<ul>
+	<li>The node of a binary tree is a <em>leaf</em> if and only if it has no children</li>
+	<li>The <em>depth</em> of the root of the tree is 0, and if the depth of a node is <code>d</code>, the depth of each of its children&nbsp;is&nbsp;<code>d+1</code>.</li>
+	<li>The <em>lowest common ancestor</em> of a set <code>S</code> of nodes is the node <code>A</code> with the largest depth such that every node in S is in the subtree with root <code>A</code>.</li>
+</ul>
+
+<p>&nbsp;</p>
+<p><strong>Example 1:</strong></p>
+
+<pre>
+<strong>Input:</strong> root = [1,2,3]
+<strong>Output:</strong> [1,2,3]
+<strong>Explanation:</strong> 
+The deepest leaves are the nodes with values 2 and 3.
+The lowest common ancestor of these leaves is the node with value 1.
+The answer returned is a TreeNode object (not an array) with serialization &quot;[1,2,3]&quot;.
+</pre>
+
+<p><strong>Example 2:</strong></p>
+
+<pre>
+<strong>Input:</strong> root = [1,2,3,4]
+<strong>Output:</strong> [4]
+</pre>
+
+<p><strong>Example 3:</strong></p>
+
+<pre>
+<strong>Input:</strong> root = [1,2,3,4,5]
+<strong>Output:</strong> [2,4,5]
+</pre>
+
+<p>&nbsp;</p>
+<p><strong>Constraints:</strong></p>
+
+<ul>
+	<li>The given tree will have between 1 and 1000 nodes.</li>
+	<li>Each node of the tree will have a distinct value between 1 and 1000.</li>
+</ul>
+
+### Related Topics
+  [[Tree](https://github.com/openset/leetcode/tree/master/tag/tree/README.md)]
+  [[Depth-first Search](https://github.com/openset/leetcode/tree/master/tag/depth-first-search/README.md)]
diff --git a/problems/maximum-average-subtree/README.md b/problems/maximum-average-subtree/README.md
@@ -0,0 +1,33 @@
+<!--|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/remove-vowels-from-a-string "Remove Vowels from a String")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/divide-array-into-increasing-sequences "Divide Array Into Increasing Sequences")
+
+## 1120. Maximum Average Subtree (Medium)
+
+
+
+### Related Topics
+  [[Tree](https://github.com/openset/leetcode/tree/master/tag/tree/README.md)]
+
+### Hints
+<details>
+<summary>Hint 1</summary>
+Can you find the sum of values and the number of nodes for every sub-tree ?
+</details>
+
+<details>
+<summary>Hint 2</summary>
+Can you find the sum of values and the number of nodes for a sub-tree given the sum of values and the number of nodes of it's left and right sub-trees ?
+</details>
+
+<details>
+<summary>Hint 3</summary>
+Use depth first search to recursively find the solution for the children of a node then use their solutions to compute the current node's solution.
+</details>
diff --git a/problems/number-of-days-in-a-month/README.md b/problems/number-of-days-in-a-month/README.md
@@ -0,0 +1,25 @@
+<!--|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/building-h2o "Building H2O")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/remove-vowels-from-a-string "Remove Vowels from a String")
+
+## 1118. Number of Days in a Month (Easy)
+
+
+
+### Hints
+<details>
+<summary>Hint 1</summary>
+Does February have 28 days or 29 days?
+</details>
+
+<details>
+<summary>Hint 2</summary>
+Think of Leap years.
+</details>
diff --git a/problems/relative-sort-array/README.md b/problems/relative-sort-array/README.md
@@ -0,0 +1,35 @@
+<!--|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/divide-array-into-increasing-sequences "Divide Array Into Increasing Sequences")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/lowest-common-ancestor-of-deepest-leaves "Lowest Common Ancestor of Deepest Leaves")
+
+## 1122. Relative Sort Array (Easy)
+
+<p>Given two arrays <code>arr1</code> and <code>arr2</code>, the elements of <code>arr2</code> are distinct, and all elements in <code>arr2</code> are also in <code>arr1</code>.</p>
+
+<p>Sort the elements of <code>arr1</code> such that the relative ordering of items in <code>arr1</code> are the same as in <code>arr2</code>.&nbsp; Elements that don&#39;t appear in <code>arr2</code> should be placed at the end of <code>arr1</code> in <strong>ascending</strong> order.</p>
+
+<p>&nbsp;</p>
+<p><strong>Example 1:</strong></p>
+<pre><strong>Input:</strong> arr1 = [2,3,1,3,2,4,6,7,9,2,19], arr2 = [2,1,4,3,9,6]
+<strong>Output:</strong> [2,2,2,1,4,3,3,9,6,7,19]
+</pre>
+<p>&nbsp;</p>
+<p><strong>Constraints:</strong></p>
+
+<ul>
+	<li><code>arr1.length, arr2.length &lt;= 1000</code></li>
+	<li><code>0 &lt;= arr1[i], arr2[i] &lt;= 1000</code></li>
+	<li>Each&nbsp;<code>arr2[i]</code>&nbsp;is&nbsp;distinct.</li>
+	<li>Each&nbsp;<code>arr2[i]</code> is in <code>arr1</code>.</li>
+</ul>
+
+### Related Topics
+  [[Array](https://github.com/openset/leetcode/tree/master/tag/array/README.md)]
+  [[Sort](https://github.com/openset/leetcode/tree/master/tag/sort/README.md)]
diff --git a/problems/remove-vowels-from-a-string/README.md b/problems/remove-vowels-from-a-string/README.md
diff --git a/problems/reverse-vowels-of-a-string/README.md b/problems/reverse-vowels-of-a-string/README.md
diff --git a/problems/smallest-sufficient-team/README.md b/problems/smallest-sufficient-team/README.md
diff --git a/problems/unique-binary-search-trees-ii/README.md b/problems/unique-binary-search-trees-ii/README.md
diff --git a/problems/unique-binary-search-trees/README.md b/problems/unique-binary-search-trees/README.md
