CF983B.XOR-pyramid

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题目描述

For an array bb of length mm we define the function ff as

$ f(b) = \begin{cases} b[1] & \quad \text{if } m = 1 \ f(b[1] \oplus b[2],b[2] \oplus b[3],\dots,b[m-1] \oplus b[m]) & \quad \text{otherwise,} \end{cases} $ where \oplus is bitwise exclusive OR.

For example, f(1,2,4,8)=f(12,24,48)=f(3,6,12)=f(36,612)=f(5,10)=f(510)=f(15)=15f(1,2,4,8)=f(1\oplus2,2\oplus4,4\oplus8)=f(3,6,12)=f(3\oplus6,6\oplus12)=f(5,10)=f(5\oplus10)=f(15)=15

You are given an array aa and a few queries. Each query is represented as two integers ll and rr . The answer is the maximum value of ff on all continuous subsegments of the array al,al+1,,ara_l, a_{l+1}, \ldots, a_r .

输入格式

The first line contains a single integer nn ( 1n50001 \le n \le 5000 ) — the length of aa .

The second line contains nn integers a1,a2,,ana_1, a_2, \dots, a_n ( 0ai23010 \le a_i \le 2^{30}-1 ) — the elements of the array.

The third line contains a single integer qq ( 1q1000001 \le q \le 100\,000 ) — the number of queries.

Each of the next qq lines contains a query represented as two integers ll , rr ( 1lrn1 \le l \le r \le n ).

输出格式

Print qq lines — the answers for the queries.

输入输出样例

  • 输入#1

    3
    8 4 1
    2
    2 3
    1 2
    

    输出#1

    5
    12
    
  • 输入#2

    6
    1 2 4 8 16 32
    4
    1 6
    2 5
    3 4
    1 2
    

    输出#2

    60
    30
    12
    3
    

说明/提示

In first sample in both queries the maximum value of the function is reached on the subsegment that is equal to the whole segment.

In second sample, optimal segment for first query are [3,6][3,6] , for second query — [2,5][2,5] , for third — [3,4][3,4] , for fourth — [1,2][1,2] .

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