title: box stacking problem
body: <p>Given are <code>n</code> boxes in three dimension (<code>h</code>, <code>w</code>, <code>d</code>). The goal is to stack them on top of each other to have a maximum height (boxes can be rotated). Each box that you put on top should have a smaller dimension (<code>w</code>, <code>d</code>) than the one below. </p>
  
  <p>How can we do it with dynamic programming and greedy?</p>