ZYBZYBZYB played a game named NumberBombNumber BombNumberBomb with his classmates in hiking:a host keeps a number in [1,N][1,N][1,N] in mind,then players guess a number in turns,the player who exactly guesses XXX loses,or the host will tell all the players that the number now is bigger or smaller than XXX.After that,the range players can guess will decrease.The range is [1,N][1,N][1,N] at first,each player should guess in the legal range.
Now if only two players are play the game,and both of two players know the XXX,if two persons all use the best strategy,and the first player guesses first.You are asked to find the number of XXX that the second player will win when XXX is in [1,N][1,N][1,N].