if(board[i][j]==0){
          board[i][j]=whomoves;                          //make the move onto the board
		  if(lvl == 3)
			{
				nn->score_ = Eval(board, whomoves, i, j);
				return nn;
			}//undo the move...this is important
			nn->child_[i][j]=CreateTree(board,lvl+1,i,j, alpha, beta);  //recursively create the //subtree
			nn->child_[i][j]->threat_ = Eval(board, -whomoves, i, j);
			nn->child_[i][j]->score_ = Eval(board, whomoves, i, j);
			board[i][j]=0;
			if(nn->child_[i][j]->score_ > beta)
			{
				beta = nn->score_;
				break;
			}
			if(nn->child_[i][j]->score_ < alpha && nn->child_[i][j]->score_ > beta)
				alpha = nn->score_;
		  }
		}
        }