update

leetcode/problem/unique-paths.html

@@ -0,0 +1,31 @@
+<p>There is a robot on an <code>m x n</code> grid. The robot is initially located at the <strong>top-left corner</strong> (i.e., <code>grid[0][0]</code>). The robot tries to move to the <strong>bottom-right corner</strong> (i.e., <code>grid[m - 1][n - 1]</code>). The robot can only move either down or right at any point in time.</p>
+
+<p>Given the two integers <code>m</code> and <code>n</code>, return <em>the number of possible unique paths that the robot can take to reach the bottom-right corner</em>.</p>
+
+<p>The test cases are generated so that the answer will be less than or equal to <code>2 * 10<sup>9</sup></code>.</p>
+
+<p>&nbsp;</p>
+<p><strong>Example 1:</strong></p>
+<img src="https://assets.leetcode.com/uploads/2018/10/22/robot_maze.png" style="width: 400px; height: 183px;" />
+<pre>
+<strong>Input:</strong> m = 3, n = 7
+<strong>Output:</strong> 28
+</pre>
+
+<p><strong>Example 2:</strong></p>
+
+<pre>
+<strong>Input:</strong> m = 3, n = 2
+<strong>Output:</strong> 3
+<strong>Explanation:</strong> From the top-left corner, there are a total of 3 ways to reach the bottom-right corner:
+1. Right -&gt; Down -&gt; Down
+2. Down -&gt; Down -&gt; Right
+3. Down -&gt; Right -&gt; Down
+</pre>
+
+<p>&nbsp;</p>
+<p><strong>Constraints:</strong></p>
+
+<ul>
+	<li><code>1 &lt;= m, n &lt;= 100</code></li>
+</ul>