word-search.md

<p>Given a 2D board and a word, find if the word exists in the grid.</p>

<p>The word can be constructed from letters of sequentially adjacent cell, where &quot;adjacent&quot; cells are those horizontally or vertically neighboring. The same letter cell may not be used more than once.</p>

<p><strong>Example:</strong></p>

<pre>
board =
[
  [&#39;A&#39;,&#39;B&#39;,&#39;C&#39;,&#39;E&#39;],
  [&#39;S&#39;,&#39;F&#39;,&#39;C&#39;,&#39;S&#39;],
  [&#39;A&#39;,&#39;D&#39;,&#39;E&#39;,&#39;E&#39;]
]

Given word = &quot;<strong>ABCCED</strong>&quot;, return <strong>true</strong>.
Given word = &quot;<strong>SEE</strong>&quot;, return <strong>true</strong>.
Given word = &quot;<strong>ABCB</strong>&quot;, return <strong>false</strong>.
</pre>