title: How do I write a recursive function for a combination
body: <p>I am going over recursive functions and i understand how to write basic ones, but I have a question on my study guide that I dont understand. </p>
  
  <p>.   Write code for a recursive function named Combinations that computes nCr. Assume that nCr can be computed as follows:</p>
  
  <pre><code>nCr = 1 if r = 0 or if r = n and
  nCr = (n-1)C(r-1) + (n-1)Cr
  </code></pre>
  
  <p>Can someone please help me through this or explain in layman's terms? Thank you!</p>