Create README - LeetHub

Author: areumH

0012-integer-to-roman/README.md

@@ -0,0 +1,108 @@
+<h2><a href="https://leetcode.com/problems/integer-to-roman">12. Integer to Roman</a></h2><h3>Medium</h3><hr><p>Seven different symbols represent Roman numerals with the following values:</p>
+
+<table>
+	<thead>
+		<tr>
+			<th>Symbol</th>
+			<th>Value</th>
+		</tr>
+	</thead>
+	<tbody>
+		<tr>
+			<td>I</td>
+			<td>1</td>
+		</tr>
+		<tr>
+			<td>V</td>
+			<td>5</td>
+		</tr>
+		<tr>
+			<td>X</td>
+			<td>10</td>
+		</tr>
+		<tr>
+			<td>L</td>
+			<td>50</td>
+		</tr>
+		<tr>
+			<td>C</td>
+			<td>100</td>
+		</tr>
+		<tr>
+			<td>D</td>
+			<td>500</td>
+		</tr>
+		<tr>
+			<td>M</td>
+			<td>1000</td>
+		</tr>
+	</tbody>
+</table>
+
+<p>Roman numerals are formed by appending&nbsp;the conversions of&nbsp;decimal place values&nbsp;from highest to lowest. Converting a decimal place value into a Roman numeral has the following rules:</p>
+
+<ul>
+	<li>If the value does not start with 4 or&nbsp;9, select the symbol of the maximal value that can be subtracted from the input, append that symbol to the result, subtract its value, and convert the remainder to a Roman numeral.</li>
+	<li>If the value starts with 4 or 9 use the&nbsp;<strong>subtractive form</strong>&nbsp;representing&nbsp;one symbol subtracted from the following symbol, for example,&nbsp;4 is 1 (<code>I</code>) less than 5 (<code>V</code>): <code>IV</code>&nbsp;and 9 is 1 (<code>I</code>) less than 10 (<code>X</code>): <code>IX</code>.&nbsp;Only the following subtractive forms are used: 4 (<code>IV</code>), 9 (<code>IX</code>),&nbsp;40 (<code>XL</code>), 90 (<code>XC</code>), 400 (<code>CD</code>) and 900 (<code>CM</code>).</li>
+	<li>Only powers of 10 (<code>I</code>, <code>X</code>, <code>C</code>, <code>M</code>) can be appended consecutively at most 3 times to represent multiples of 10. You cannot append 5&nbsp;(<code>V</code>), 50 (<code>L</code>), or 500 (<code>D</code>) multiple times. If you need to append a symbol&nbsp;4 times&nbsp;use the <strong>subtractive form</strong>.</li>
+</ul>
+
+<p>Given an integer, convert it to a Roman numeral.</p>
+
+<p>&nbsp;</p>
+<p><strong class="example">Example 1:</strong></p>
+
+<div class="example-block">
+<p><strong>Input:</strong> <span class="example-io">num = 3749</span></p>
+
+<p><strong>Output:</strong> <span class="example-io">&quot;MMMDCCXLIX&quot;</span></p>
+
+<p><strong>Explanation:</strong></p>
+
+<pre>
+3000 = MMM as 1000 (M) + 1000 (M) + 1000 (M)
+ 700 = DCC as 500 (D) + 100 (C) + 100 (C)
+  40 = XL as 10 (X) less of 50 (L)
+   9 = IX as 1 (I) less of 10 (X)
+Note: 49 is not 1 (I) less of 50 (L) because the conversion is based on decimal places
+</pre>
+</div>
+
+<p><strong class="example">Example 2:</strong></p>
+
+<div class="example-block">
+<p><strong>Input:</strong> <span class="example-io">num = 58</span></p>
+
+<p><strong>Output:</strong> <span class="example-io">&quot;LVIII&quot;</span></p>
+
+<p><strong>Explanation:</strong></p>
+
+<pre>
+50 = L
+ 8 = VIII
+</pre>
+</div>
+
+<p><strong class="example">Example 3:</strong></p>
+
+<div class="example-block">
+<p><strong>Input:</strong> <span class="example-io">num = 1994</span></p>
+
+<p><strong>Output:</strong> <span class="example-io">&quot;MCMXCIV&quot;</span></p>
+
+<p><strong>Explanation:</strong></p>
+
+<pre>
+1000 = M
+ 900 = CM
+  90 = XC
+   4 = IV
+</pre>
+</div>
+
+<p>&nbsp;</p>
+<p><strong>Constraints:</strong></p>
+
+<ul>
+	<li><code>1 &lt;= num &lt;= 3999</code></li>
+</ul>