title: Remove all blue nodes from the tree
body: <p>Given a binary tree with nodes having color attribute. The tree has red nodes and blue nodes.</p>
  
  <p>Remove all blue nodes from the tree and return a tree with only the red nodes?</p>
  
  <p>I have tried to implement this like this:</p>
  
  <pre><code>Node stripblue(Node root)
  {
      if(root.left != NULL)
        root.left = stripblue(root.left) //is this line correct ? //TODO
  
      if(root.right != NULL)
         root.right = stripblue(root.right) // is this line correct ? //TODO
  
       if(root.color == RED)
       return root
  }
  </code></pre>
  
  <p>I am having some trouble wrapping my head on implementing the <code>TODO</code> part of my algorithm. Can someone give me some ideas?</p>