title: Use sort for multidimensional array (array in array) in Swift?
body: <p>I want to know that how can we use <code>sort</code> or <code>sorted</code> function for multidimensional array in Swift?</p>
  
  <p>For example theirs an array:</p>
  
  <pre><code>[
      [5, "test888"],
      [3, "test663"],
      [2, "test443"],
      [1, "test123"]
  ]
  </code></pre>
  
  <p>And I want to sort it via the first ID's low to high:</p>
  
  <pre><code>[
      [1, "test123"],
      [2, "test443"],
      [3, "test663"],
      [5, "test888"]
  ]
  </code></pre>
  
  <p>So how can we do this? Thanks!</p>