Add: new

README.md

@@ -53,6 +53,10 @@ LeetCode Problems' Solutions
 
 | # | Title | Solution | Difficulty |
 | :-: | - | - | :-: |
+| <span id="976">976</span> | [Largest Perimeter Triangle](https://leetcode.com/problems/largest-perimeter-triangle "三角形的最大周长") | [Go](https://github.com/openset/leetcode/tree/master/problems/largest-perimeter-triangle) | Easy |
+| <span id="975">975</span> | [Odd Even Jump](https://leetcode.com/problems/odd-even-jump "奇偶跳") | [Go](https://github.com/openset/leetcode/tree/master/problems/odd-even-jump) | Hard |
+| <span id="974">974</span> | [Subarray Sums Divisible by K](https://leetcode.com/problems/subarray-sums-divisible-by-k "和可被 K 整除的子数组") | [Go](https://github.com/openset/leetcode/tree/master/problems/subarray-sums-divisible-by-k) | Medium |
+| <span id="973">973</span> | [K Closest Points to Origin](https://leetcode.com/problems/k-closest-points-to-origin "最接近原点的 K 个点") | [Go](https://github.com/openset/leetcode/tree/master/problems/k-closest-points-to-origin) | Easy |
 | <span id="972">972</span> | [Equal Rational Numbers](https://leetcode.com/problems/equal-rational-numbers "相等的有理数") | [Go](https://github.com/openset/leetcode/tree/master/problems/equal-rational-numbers) | Hard |
 | <span id="971">971</span> | [Flip Binary Tree To Match Preorder Traversal](https://leetcode.com/problems/flip-binary-tree-to-match-preorder-traversal "翻转二叉树以匹配先序遍历") | [Go](https://github.com/openset/leetcode/tree/master/problems/flip-binary-tree-to-match-preorder-traversal) | Medium |
 | <span id="970">970</span> | [Powerful Integers](https://leetcode.com/problems/powerful-integers "强整数") | [Go](https://github.com/openset/leetcode/tree/master/problems/powerful-integers) | Easy |
@@ -989,7 +993,7 @@ LeetCode Problems' Solutions
 | <span id="33">33</span> | [Search in Rotated Sorted Array](https://leetcode.com/problems/search-in-rotated-sorted-array "搜索旋转排序数组") | [Go](https://github.com/openset/leetcode/tree/master/problems/search-in-rotated-sorted-array) | Medium |
 | <span id="32">32</span> | [Longest Valid Parentheses](https://leetcode.com/problems/longest-valid-parentheses "最长有效括号") | [Go](https://github.com/openset/leetcode/tree/master/problems/longest-valid-parentheses) | Hard |
 | <span id="31">31</span> | [Next Permutation](https://leetcode.com/problems/next-permutation "下一个排列") | [Go](https://github.com/openset/leetcode/tree/master/problems/next-permutation) | Medium |
-| <span id="30">30</span> | [Substring with Concatenation of All Words](https://leetcode.com/problems/substring-with-concatenation-of-all-words "与所有单词相关联的字串") | [Go](https://github.com/openset/leetcode/tree/master/problems/substring-with-concatenation-of-all-words) | Hard |
+| <span id="30">30</span> | [Substring with Concatenation of All Words](https://leetcode.com/problems/substring-with-concatenation-of-all-words "串联所有单词的子串") | [Go](https://github.com/openset/leetcode/tree/master/problems/substring-with-concatenation-of-all-words) | Hard |
 | <span id="29">29</span> | [Divide Two Integers](https://leetcode.com/problems/divide-two-integers "两数相除") | [Go](https://github.com/openset/leetcode/tree/master/problems/divide-two-integers) | Medium |
 | <span id="28">28</span> | [Implement strStr()](https://leetcode.com/problems/implement-strstr "实现strStr()") | [Go](https://github.com/openset/leetcode/tree/master/problems/implement-strstr) | Easy |
 | <span id="27">27</span> | [Remove Element](https://leetcode.com/problems/remove-element "移除元素") | [Go](https://github.com/openset/leetcode/tree/master/problems/remove-element) | Easy |

problems/k-closest-points-to-origin/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                        |-->
+<!--+----------------------------------------------------------------------+-->
+
+## 973. K Closest Points to Origin (Easy)
+
+<p>We have a list of <code>points</code>&nbsp;on the plane.&nbsp; Find the <code>K</code> closest points to the origin <code>(0, 0)</code>.</p>
+
+<p>(Here, the distance between two points on a plane is the Euclidean distance.)</p>
+
+<p>You may return the answer in any order.&nbsp; The&nbsp;answer is guaranteed to be unique (except for the order that it is in.)</p>
+
+<p>&nbsp;</p>
+
+<div>
+<p><strong>Example 1:</strong></p>
+
+<pre>
+<strong>Input: </strong>points = <span id="example-input-1-1">[[1,3],[-2,2]]</span>, K = <span id="example-input-1-2">1</span>
+<strong>Output: </strong><span id="example-output-1">[[-2,2]]</span>
+<strong>Explanation: </strong>
+The distance between (1, 3) and the origin is sqrt(10).
+The distance between (-2, 2) and the origin is sqrt(8).
+Since sqrt(8) &lt; sqrt(10), (-2, 2) is closer to the origin.
+We only want the closest K = 1 points from the origin, so the answer is just [[-2,2]].
+</pre>
+
+<div>
+<p><strong>Example 2:</strong></p>
+
+<pre>
+<strong>Input: </strong>points = <span id="example-input-2-1">[[3,3],[5,-1],[-2,4]]</span>, K = <span id="example-input-2-2">2</span>
+<strong>Output: </strong><span id="example-output-2">[[3,3],[-2,4]]</span>
+(The answer [[-2,4],[3,3]] would also be accepted.)
+</pre>
+
+<p>&nbsp;</p>
+
+<p><strong>Note:</strong></p>
+
+<ol>
+	<li><code>1 &lt;= K &lt;= points.length &lt;= 10000</code></li>
+	<li><code>-10000 &lt; points[i][0] &lt; 10000</code></li>
+	<li><code>-10000 &lt; points[i][1] &lt; 10000</code></li>
+</ol>
+</div>
+</div>
+
+
+### Related Topics
+  [[Sort](https://github.com/openset/leetcode/tree/master/tag/sort/README.md)]
+  [[Math](https://github.com/openset/leetcode/tree/master/tag/math/README.md)]
+  [[Divide and Conquer](https://github.com/openset/leetcode/tree/master/tag/divide-and-conquer/README.md)]

problems/largest-perimeter-triangle/README.md

@@ -0,0 +1,67 @@
+<!--|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                        |-->
+<!--+----------------------------------------------------------------------+-->
+
+## 976. Largest Perimeter Triangle (Easy)
+
+<p>Given an array <code>A</code> of positive lengths, return the largest perimeter of a triangle with <strong>non-zero area</strong>, formed from 3 of these lengths.</p>
+
+<p>If it is impossible to form any&nbsp;triangle of non-zero area, return <code>0</code>.</p>
+
+<p>&nbsp;</p>
+
+<ol>
+</ol>
+
+<div>
+<p><strong>Example 1:</strong></p>
+
+<pre>
+<strong>Input: </strong><span id="example-input-1-1">[2,1,2]</span>
+<strong>Output: </strong><span id="example-output-1">5</span>
+</pre>
+
+<div>
+<p><strong>Example 2:</strong></p>
+
+<pre>
+<strong>Input: </strong><span id="example-input-2-1">[1,2,1]</span>
+<strong>Output: </strong><span id="example-output-2">0</span>
+</pre>
+
+<div>
+<p><strong>Example 3:</strong></p>
+
+<pre>
+<strong>Input: </strong><span id="example-input-3-1">[3,2,3,4]</span>
+<strong>Output: </strong><span id="example-output-3">10</span>
+</pre>
+
+<div>
+<p><strong>Example 4:</strong></p>
+
+<pre>
+<strong>Input: </strong><span id="example-input-4-1">[3,6,2,3]</span>
+<strong>Output: </strong><span id="example-output-4">8</span>
+</pre>
+
+<p>&nbsp;</p>
+
+<p><strong>Note:</strong></p>
+
+<ol>
+	<li><code>3 &lt;= A.length &lt;= 10000</code></li>
+	<li><code>1 &lt;= A[i] &lt;= 10^6</code></li>
+</ol>
+</div>
+</div>
+</div>
+</div>
+
+
+### Related Topics
+  [[Array](https://github.com/openset/leetcode/tree/master/tag/array/README.md)]
+  [[Math](https://github.com/openset/leetcode/tree/master/tag/math/README.md)]

problems/odd-even-jump/README.md

@@ -0,0 +1,88 @@
+<!--|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                        |-->
+<!--+----------------------------------------------------------------------+-->
+
+## 975. Odd Even Jump (Hard)
+
+<p>You are given an integer array <code>A</code>.&nbsp; From&nbsp;some starting index, you can make a series of jumps.&nbsp; The (1st, 3rd, 5th, ...)&nbsp;jumps in the series are called <em>odd numbered jumps</em>, and the (2nd, 4th, 6th, ...) jumps in the series are called <em>even numbered jumps</em>.</p>
+
+<p>You may from index <code>i</code>&nbsp;jump forward to index <code><font face="monospace">j</font></code>&nbsp;(with <code>i&nbsp;&lt; j</code>) in the following way:</p>
+
+<ul>
+	<li>During odd numbered jumps (ie. jumps 1, 3, 5, ...), you jump to the index <font face="monospace">j</font>&nbsp;such that <code>A[i] &lt;= A[j]</code> and <code>A[j]</code> is the smallest possible value.&nbsp; If there are multiple such indexes <code><font face="monospace">j</font></code>, you can only jump to the <strong>smallest</strong> such index <code><font face="monospace">j</font></code>.</li>
+	<li>During even numbered jumps (ie. jumps 2, 4, 6, ...), you jump to the index <font face="monospace">j</font>&nbsp;such that <code>A[i] &gt;= A[j]</code> and <code>A[j]</code> is the largest&nbsp;possible value.&nbsp; If there are multiple such indexes <code><font face="monospace">j</font></code>, you can only jump to the <strong>smallest</strong> such index <code><font face="monospace">j</font></code>.</li>
+	<li>(It may be the case that for some index <code><font face="monospace">i</font>,</code> there are no legal jumps.)</li>
+</ul>
+
+<p>A starting index is <em>good</em> if, starting from that index, you can reach the end of the array (index <code>A.length - 1</code>) by jumping some number of times (possibly 0 or more than once.)</p>
+
+<p>Return the number of good starting indexes.</p>
+
+<p>&nbsp;</p>
+
+<p><strong>Example 1:</strong></p>
+
+<pre>
+<strong>Input: </strong><span id="example-input-1-1">[10,13,12,14,15]</span>
+<strong>Output: </strong><span id="example-output-1">2</span>
+<strong>Explanation: </strong>
+From starting index i = 0, we can jump to i = 2 (since A[2] is the smallest among A[1], A[2], A[3], A[4] that is greater or equal to A[0]), then we can&#39;t jump any more.
+From starting index i = 1 and i = 2, we can jump to i = 3, then we can&#39;t jump any more.
+From starting index i = 3, we can jump to i = 4, so we&#39;ve reached the end.
+From starting index i = 4, we&#39;ve reached the end already.
+In total, there are 2 different starting indexes (i = 3, i = 4) where we can reach the end with some number of jumps.
+</pre>
+
+<div>
+<p><strong>Example 2:</strong></p>
+
+<pre>
+<strong>Input: </strong><span id="example-input-2-1">[2,3,1,1,4]</span>
+<strong>Output: </strong><span id="example-output-2">3</span>
+<strong>Explanation: </strong>
+From starting index i = 0, we make jumps to i = 1, i = 2, i = 3:
+
+During our 1st jump (odd numbered), we first jump to i = 1 because A[1] is the smallest value in (A[1], A[2], A[3], A[4]) that is greater than or equal to A[0].
+
+During our 2nd jump (even numbered), we jump from i = 1 to i = 2 because A[2] is the largest value in (A[2], A[3], A[4]) that is less than or equal to A[1].  A[3] is also the largest value, but 2 is a smaller index, so we can only jump to i = 2 and not i = 3.
+
+During our 3rd jump (odd numbered), we jump from i = 2 to i = 3 because A[3] is the smallest value in (A[3], A[4]) that is greater than or equal to A[2].
+
+We can&#39;t jump from i = 3 to i = 4, so the starting index i = 0 is not good.
+
+In a similar manner, we can deduce that:
+From starting index i = 1, we jump to i = 4, so we reach the end.
+From starting index i = 2, we jump to i = 3, and then we can&#39;t jump anymore.
+From starting index i = 3, we jump to i = 4, so we reach the end.
+From starting index i = 4, we are already at the end.
+In total, there are 3 different starting indexes (i = 1, i = 3, i = 4) where we can reach the end with some number of jumps.
+</pre>
+
+<div>
+<p><strong>Example 3:</strong></p>
+
+<pre>
+<strong>Input: </strong><span id="example-input-3-1">[5,1,3,4,2]</span>
+<strong>Output: </strong><span id="example-output-3">3</span>
+<strong>Explanation: </strong>
+We can reach the end from starting indexes 1, 2, and 4.
+</pre>
+</div>
+</div>
+
+<p>&nbsp;</p>
+
+<p><strong>Note:</strong></p>
+
+<ol>
+	<li><code>1 &lt;= A.length &lt;= 20000</code></li>
+	<li><code>0 &lt;= A[i] &lt; 100000</code></li>
+</ol>
+
+
+### Related Topics
+  [[Stack](https://github.com/openset/leetcode/tree/master/tag/stack/README.md)]
+  [[Dynamic Programming](https://github.com/openset/leetcode/tree/master/tag/dynamic-programming/README.md)]

problems/subarray-sums-divisible-by-k/README.md

@@ -0,0 +1,37 @@
+<!--|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                        |-->
+<!--+----------------------------------------------------------------------+-->
+
+## 974. Subarray Sums Divisible by K (Medium)
+
+<p>Given an array <code>A</code> of integers, return the number of (contiguous, non-empty) subarrays that have a sum divisible by <code>K</code>.</p>
+
+<p>&nbsp;</p>
+
+<div>
+<p><strong>Example 1:</strong></p>
+
+<pre>
+<strong>Input: </strong>A = <span id="example-input-1-1">[4,5,0,-2,-3,1]</span>, K = <span id="example-input-1-2">5</span>
+<strong>Output: </strong><span id="example-output-1">7</span>
+<strong>Explanation: </strong>There are 7 subarrays with a sum divisible by K = 5:
+[4, 5, 0, -2, -3, 1], [5], [5, 0], [5, 0, -2, -3], [0], [0, -2, -3], [-2, -3]
+</pre>
+
+<p>&nbsp;</p>
+
+<p><strong>Note:</strong></p>
+
+<ol>
+	<li><code>1 &lt;= A.length &lt;= 30000</code></li>
+	<li><code>-10000 &lt;= A[i] &lt;= 10000</code></li>
+	<li><code>2 &lt;= K &lt;= 10000</code></li>
+</ol>
+</div>
+
+
+### Related Topics
+  [[Array](https://github.com/openset/leetcode/tree/master/tag/array/README.md)]