Codeforces Round 483 (Div. 1) [Thanks, Botan Investments and Victor Shaburov!]
B
XOR-pyramid
Codeforces
1800
原题
← AC →
翻译中…

For an array $b$ of length $m$ we define the function $f$ as

翻译中…

$ 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} $

翻译中…

where $\oplus$ is bitwise exclusive OR.

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

翻译中…

You are given an array $a$ and a few queries. Each query is represented as two integers $l$ and $r$. The answer is the maximum value of $f$ on all continuous subsegments of the array $a_l, a_{l+1}, \ldots, a_r$.

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Input

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

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The second line contains $n$ integers $a_1, a_2, \dots, a_n$ ($0 \le a_i \le 2^{30}-1$) — the elements of the array.

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

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Each of the next $q$ lines contains a query represented as two integers $l$, $r$ ($1 \le l \le r \le n$).

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Output

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Print $q$ lines — the answers for the queries.

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Note

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

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

翻译中…

样例

Input #1
3
8 4 1
2
2 3
1 2
Output #1
5
12
InputCopy OutputCopy
Input #2
6
1 2 4 8 16 32
4
1 6
2 5
3 4
1 2
Output #2
60
30
12
3
InputCopy OutputCopy
题目信息
题号
983B
时间限制
2 s
内存限制
512 MB
标签
动态规划

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