Distributed Median,Alice has an array A, and Bob has an array B. All elements in A and B are distinct. Alice and Bob are interested in finding the median element of their combined arrays.
假定已經有許多應用采用了程序1 - 1 5中所定義的C u r r e n c y類，現在我們想要對C u r r e n c y類
的描述進行修改，使其應用頻率最高的兩個函數A d d和I n c r e m e n t可以運行得更快，從而提高應
用程序的執行速度。由于用戶僅能通過p u b l i c部分所提供的接口與C u r r e n c y類進行交互，
