title: How do I solve the 'classic' knapsack algorithm recursively?
body: <p>This is my task</p>
  
  <blockquote>
    <p>The Knapsack Problem is a classic in computer science. In its simplest
    form it involves trying to fit items of different weights into a
    knapsack so that the knapsack ends up with a specified total weight.
    You don't need to fit in all the items. For example, suppose you want
    your knapsack to weigh exactly 20 pounds, and you have five items,
    with weights of 11, 8, 7, 6, and 5 pounds. For small numbers of items,
    humans are pretty good at solving this problem by inspection. So you
    can probably figure out that only the 8, 7, and 5 combination of items
    adds up to 20.</p>
  </blockquote>
  
  <p>I really don't know where to begin writing this algorithm. I understand recursion when applied to factorials and triangle numbers. However I'm lost right now.</p>