title: comparing two arrays before adding an item from one array to another in JavaScript
body: <p>I have two arrays.</p>
  
  <pre><code>var addFrom = ["orange", "banana", "watermelon", "lemon", "peach"];
  var addTo = ["pear", "tangerine", "grape", "orange", "blueberry"];
  </code></pre>
  
  <p>I would like to check if the first item in "addFrom" array is already in "addTo" array.</p>
  
  <p>If the "addTo" array does not have the first item in "addFrom" array, I would like to push this item to "addTo" array.</p>
  
  <p>However, if the first item in the "addFrom" array is already in the "addTo" array, I would like to move on to the second item in the "addFrom" array and do the same thing until I find the item in the "addFrom" array that is not in the "addTo" array, which will then be pushed to the "addTo" array. and I want to add only one item to the "addTo" array.</p>
  
  <p>As a result, I want the "addTo" array to look like this:</p>
  
  <pre><code>var addTo = ["pear", "tangerine", "grape", "orange", "blueberry", "banana"];
  </code></pre>
  
  <p>How can I do this in JavaScript?</p>