Create README - LeetHub

38-count-and-say/README.md

@@ -0,0 +1,39 @@
+<h2><a href="https://leetcode.com/problems/count-and-say/">38. Count and Say</a></h2><h3>Medium</h3><hr><div><p>The <strong>count-and-say</strong> sequence is a sequence of digit strings defined by the recursive formula:</p>
+
+<ul>
+	<li><code>countAndSay(1) = "1"</code></li>
+	<li><code>countAndSay(n)</code> is the way you would "say" the digit string from <code>countAndSay(n-1)</code>, which is then converted into a different digit string.</li>
+</ul>
+
+<p>To determine how you "say" a digit string, split it into the <strong>minimal</strong> number of substrings such that each substring contains exactly <strong>one</strong> unique digit. Then for each substring, say the number of digits, then say the digit. Finally, concatenate every said digit.</p>
+
+<p>For example, the saying and conversion for digit string <code>"3322251"</code>:</p>
+<img alt="" src="https://assets.leetcode.com/uploads/2020/10/23/countandsay.jpg" style="width: 581px; height: 172px;">
+<p>Given a positive integer <code>n</code>, return <em>the </em><code>n<sup>th</sup></code><em> term of the <strong>count-and-say</strong> sequence</em>.</p>
+
+<p>&nbsp;</p>
+<p><strong>Example 1:</strong></p>
+
+<pre><strong>Input:</strong> n = 1
+<strong>Output:</strong> "1"
+<strong>Explanation:</strong> This is the base case.
+</pre>
+
+<p><strong>Example 2:</strong></p>
+
+<pre><strong>Input:</strong> n = 4
+<strong>Output:</strong> "1211"
+<strong>Explanation:</strong>
+countAndSay(1) = "1"
+countAndSay(2) = say "1" = one 1 = "11"
+countAndSay(3) = say "11" = two 1's = "21"
+countAndSay(4) = say "21" = one 2 + one 1 = "12" + "11" = "1211"
+</pre>
+
+<p>&nbsp;</p>
+<p><strong>Constraints:</strong></p>
+
+<ul>
+	<li><code>1 &lt;= n &lt;= 30</code></li>
+</ul>
+</div>