title: Finding the Max value in a two dimensional Array
body: <p>I'm trying to find an elegant way to find the max value in a two-dimensional array.
  for example for this array:</p>
  
  <pre><code>[0, 0, 1, 0, 0, 1] [0, 1, 0, 2, 0, 0][0, 0, 2, 0, 0, 1][0, 1, 0, 3, 0, 0][0, 0, 0, 0, 4, 0]
  </code></pre>
  
  <p>I would like to extract the value '4'.
  I thought of doing a max within max but I'm struggling in executing it.</p>