title: Check if array contains different values
body: <p>How can I make a native javascript function to detect different values in Array?</p>
  
  <p>e.g:</p>
  
  <pre><code>const arr = [];
  console.log(checkDiff(arr["A", "A", "A", "A")); // false
  console.log(checkDiff(arr["A", "A", "A", "B")); // true
  console.log(checkDiff(arr["B", "A", "C", "A")); // true
  ...
  </code></pre>
  
  <p>Thank you.</p>