CF280B Maximum Xor Secondary

Description

Bike loves looking for the second maximum element in the sequence. The second maximum element in the sequence of distinct numbers $ x_{1},x_{2},...,x_{k} $ $ (k>1) $ is such maximum element $ x_{j} $ , that the following inequality holds: ![](https://cdn.luogu.com.cn/upload/vjudge_pic/CF280B/cbffb592db1e3f6cc63c23bba8878833c080a3b3.png). The lucky number of the sequence of distinct positive integers $ x_{1},x_{2},...,x_{k} $ $ (k>1) $ is the number that is equal to the bitwise excluding OR of the maximum element of the sequence and the second maximum element of the sequence. You've got a sequence of distinct positive integers $ s_{1},s_{2},...,s_{n} $ $ (n>1) $ . Let's denote sequence $ s_{l},s_{l+1},...,s_{r} $ as $ s[l..r] $ $ (1

Input Format

N/A

Output Format

N/A

Explanation/Hint

For the first sample you can choose $ s[4..5]={4,3} $ and its lucky number is $ (4 xor 3)=7 $ . You can also choose $ s[1..2] $ . For the second sample you must choose $ s[2..5]={8,3,5,7} $ .