public void Insert(int d)
 {
     if (d <= Data)
     {
         if (Left == null)
         {
             Left = new RankNode(d);
         }
         else
         {
             Left.Insert(d);
         }
         LeftSize++;
     }
     else
     {
         if (Right == null)
         {
             Right = new RankNode(d);
         }
         else
         {
             Right.Insert(d);
         }
     }
 }
 public void track(int num)
 {
     if (root == null)
     {
         root = new RankNode(num);
     }
     else
     {
         root.Insert(num);
     }
 }