title: Scala Collections: Using a value of Set find the key from a Map object.
body: <p>This is a scala question. </p>
  
  <p>I currently have the following two collections objects:</p>
  
  <pre><code>val keywordLookup = Map("a" -&gt; "1111",
                   "b" -&gt; "2222",
                   "c" -&gt; "3333",
                   "d" -&gt; "4444",
                   "e" -&gt; "5555")
  
  val keywordList = Set("1111", "3333")
  </code></pre>
  
  <p>The keywordLookup is a lookup object. The keywordList contains a list of values that I need to find the Ids from the keywordLookup object. </p>
  
  <p>I would like the get the following result:</p>
  
  <pre><code>Map("a" -&gt; "1111", "c" -&gt; "3333")
  </code></pre>