Creating leaf node 0 [A]
Node 0 item: 'A'.
Has node 0 left child? : N.
Has node 0 right child? : N.
Creating leaf node 1 [B]
Node 1 item: 'B'.
Has node 1 left child? : N.
Has node 1 right child? : N.
Created node 2 [C] left_idx:0 right_idx:1
Node 2 item: 'C'.
Has node 2 left child? : Y.
Has node 2 right child? : Y.
Node 2 left child item: 'A'.
Node 2 right child item: 'B'.