title: How to find all possible n-elements subsets of a set?
body: <p>For a set of <code>k</code>-elements, I need to find all possible <code>n</code>-element subsets <code>(n &lt; k)</code>. </p>
  
  <p>How should I approach this problem? </p>
  
  <p>Just a suggestion will be helpful Thanks!</p>