<h2><a href="https://leetcode.com/problems/replace-words/">648. Replace Words</a></h2><h3>Medium</h3><hr><div><p>In English, we have a concept called <strong>root</strong>, which can be followed by some other word to form another longer word - let's call this word <strong>derivative</strong>. For example, when the <strong>root</strong> <code>"help"</code> is followed by the word <code>"ful"</code>, we can form a derivative <code>"helpful"</code>.</p>

<p>Given a <code>dictionary</code> consisting of many <strong>roots</strong> and a <code>sentence</code> consisting of words separated by spaces, replace all the derivatives in the sentence with the <strong>root</strong> forming it. If a derivative can be replaced by more than one <strong>root</strong>, replace it with the <strong>root</strong> that has <strong>the shortest length</strong>.</p>

<p>Return <em>the <code>sentence</code></em> after the replacement.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<pre><strong>Input:</strong> dictionary = ["cat","bat","rat"], sentence = "the cattle was rattled by the battery"
<strong>Output:</strong> "the cat was rat by the bat"
</pre>

<p><strong class="example">Example 2:</strong></p>

<pre><strong>Input:</strong> dictionary = ["a","b","c"], sentence = "aadsfasf absbs bbab cadsfafs"
<strong>Output:</strong> "a a b c"
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>1 &lt;= dictionary.length &lt;= 1000</code></li>
	<li><code>1 &lt;= dictionary[i].length &lt;= 100</code></li>
	<li><code>dictionary[i]</code> consists of only lower-case letters.</li>
	<li><code>1 &lt;= sentence.length &lt;= 10<sup>6</sup></code></li>
	<li><code>sentence</code> consists of only lower-case letters and spaces.</li>
	<li>The number of words in <code>sentence</code> is in the range <code>[1, 1000]</code></li>
	<li>The length of each word in <code>sentence</code> is in the range <code>[1, 1000]</code></li>
	<li>Every two consecutive words in <code>sentence</code> will be separated by exactly one space.</li>
	<li><code>sentence</code> does not have leading or trailing spaces.</li>
</ul>
</div>