Function to get the count of half Nodes in a binary tree
static int gethalfCount ( Node root ) { if ( root == null ) return 0 ; int res = 0 ; if ( ( root . left == null && root . right != null ) || ( root . left != null && root . right == null ) ) res ++ ; res += ( gethalfCount ( root . left ) + gethalfCount ( root . right ) ) ; return res ; }