feat: add solutions to lc problems

* No.0028.Find the Index of the First Occurrence in a String
* No.0484.Find Permutation

Author: yanglbme

solution/0000-0099/0028.Implement strStr()/README.md renamed to solution/0000-0099/0028.Find the Index of the First Occurrence in a String/README.md

@@ -1,6 +1,6 @@
-# [28. 实现 strStr()](https://leetcode.cn/problems/implement-strstr)
+# [28. 实现 strStr()](https://leetcode.cn/problems/find-the-index-of-the-first-occurrence-in-a-string)
 
-[English Version](/solution/0000-0099/0028.Implement%20strStr%28%29/README_EN.md)
+[English Version](/solution/0000-0099/0028.Find%20the%20Index%20of%20the%20First%20Occurrence%20in%20a%20String/README_EN.md)
 
 ## 题目描述
 
@@ -41,6 +41,7 @@
 	<li><code>haystack</code> 和 <code>needle</code> 仅由小写英文字符组成</li>
 </ul>
 
+
 ## 解法
 
 <!-- 这里可写通用的实现逻辑 -->

solution/0000-0099/0028.Implement strStr()/README_EN.md renamed to solution/0000-0099/0028.Find the Index of the First Occurrence in a String/README_EN.md

@@ -1,32 +1,27 @@
-# [28. Implement strStr()](https://leetcode.com/problems/implement-strstr)
+# [28. Find the Index of the First Occurrence in a String](https://leetcode.com/problems/find-the-index-of-the-first-occurrence-in-a-string)
 
-[中文文档](/solution/0000-0099/0028.Implement%20strStr%28%29/README.md)
+[中文文档](/solution/0000-0099/0028.Find%20the%20Index%20of%20the%20First%20Occurrence%20in%20a%20String/README.md)
 
 ## Description
 
-<p>Implement <a href="http://www.cplusplus.com/reference/cstring/strstr/" target="_blank">strStr()</a>.</p>
-
 <p>Given two strings <code>needle</code> and <code>haystack</code>, return the index of the first occurrence of <code>needle</code> in <code>haystack</code>, or <code>-1</code> if <code>needle</code> is not part of <code>haystack</code>.</p>
 
-<p><strong>Clarification:</strong></p>
-
-<p>What should we return when <code>needle</code> is an empty string? This is a great question to ask during an interview.</p>
-
-<p>For the purpose of this problem, we will return 0 when <code>needle</code> is an empty string. This is consistent to C&#39;s <a href="http://www.cplusplus.com/reference/cstring/strstr/" target="_blank">strstr()</a> and Java&#39;s <a href="https://docs.oracle.com/javase/7/docs/api/java/lang/String.html#indexOf(java.lang.String)" target="_blank">indexOf()</a>.</p>
-
 <p>&nbsp;</p>
-<p><strong>Example 1:</strong></p>
+<p><strong class="example">Example 1:</strong></p>
 
 <pre>
-<strong>Input:</strong> haystack = &quot;hello&quot;, needle = &quot;ll&quot;
-<strong>Output:</strong> 2
+<strong>Input:</strong> haystack = &quot;sadbutsad&quot;, needle = &quot;sad&quot;
+<strong>Output:</strong> 0
+<strong>Explanation:</strong> &quot;sad&quot; occurs at index 0 and 6.
+The first occurrence is at index 0, so we return 0.
 </pre>
 
-<p><strong>Example 2:</strong></p>
+<p><strong class="example">Example 2:</strong></p>
 
 <pre>
-<strong>Input:</strong> haystack = &quot;aaaaa&quot;, needle = &quot;bba&quot;
+<strong>Input:</strong> haystack = &quot;leetcode&quot;, needle = &quot;leeto&quot;
 <strong>Output:</strong> -1
+<strong>Explanation:</strong> &quot;leeto&quot; did not occur in &quot;leetcode&quot;, so we return -1.
 </pre>
 
 <p>&nbsp;</p>
@@ -37,6 +32,7 @@
 	<li><code>haystack</code> and <code>needle</code> consist of only lowercase English characters.</li>
 </ul>
 
+
 ## Solutions
 
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