title: Create a function that returns unique random numbers and assigns that number to an individual variable
body: <p>I am just getting started in programming and ran into this issue. The answers posted on the forum don't really help me out so here goes my question.
  I am trying to create a function that generates four random numbers between 1-12. Once the numbers are generated, they are assigned to a individual variable.  </p>
  
  <pre><code>var gem1;
  var gem2;
  var gem3;
  var gem4;
  
  function updateGem() {
      gem1 = Math.floor(Math.random() * 12 + 1);
      gem2 = Math.floor(Math.random() * 12 + 1);
      gem3 = Math.floor(Math.random() * 12 + 1);
      gem4 = Math.floor(Math.random() * 12 + 1);
  }
  
  </code></pre>
  
  <p>As you can see sometimes the numbers generated are matching, which is not what I need. I need every var to have it's own unique number. </p>
  
  <pre><code>The value of gem 1 is 8
  The value of gem 2 is 9
  The value of gem 3 is 9
  The value of gem 4 is 8
  </code></pre>