Strobogrammatic Number II
<p>Given an integer <code>n</code>, return all the <strong>strobogrammatic numbers</strong> that are of length <code>n</code>. You may return the answer in <strong>any order</strong>.</p>

<p>A <strong>strobogrammatic number</strong> is a number that looks the same when rotated <code>180</code> degrees (looked at upside down).</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>
<pre><strong>Input:</strong> n = 2
<strong>Output:</strong> ["11","69","88","96"]
</pre><p><strong class="example">Example 2:</strong></p>
<pre><strong>Input:</strong> n = 1
<strong>Output:</strong> ["0","1","8"]
</pre>
<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>1 &lt;= n &lt;= 14</code></li>
</ul>
Recursion; Array; String
class Solution:
    def findStrobogrammatic(self, n: int) -> List[str]:
        def dfs(u):
            if u == 0:
                return ['']
            if u == 1:
                return ['0', '1', '8']
            ans = []
            for v in dfs(u - 2):
                for l, r in ('11', '88', '69', '96'):
                    ans.append(l + v + r)
                if u != n:
                    ans.append('0' + v + '0')
            return ans

        return dfs(n)
