P10690 Fotile Mock Contest L

FOTILE is given a sequence $A$ of length $N$. To save the Earth, he wants to know the maximum subarray $\rm XOR$ sum within certain intervals. That is, for each query, you need to compute $$ \max_{l\le i\le j\le r}\bigoplus_{k=i}^{j} a_k $$ To reflect online operations, for a query $(x,y)$: - $l = \min ( ((x+{\rm lastans}) \bmod N)+1 , ((y+{\rm lastans}) \bmod N)+1)$. - $r = \max ( ((x+{\rm lastans}) \bmod N)+1 , ((y+{\rm lastans}) \bmod N)+1)$. **Here $\rm lastans$ is the answer to the previous query, and it is $0$ at the beginning.**

The first line contains two integers $N$ and $M$. The second line contains $N$ positive integers, where the $i$-th number is $A_i$, and there may be extra spaces. The next $M$ lines each contain two numbers $x$ and $y$, representing a query.

Output $M$ lines. The $i$-th line contains one positive integer, the answer to the $i$-th query.

For all testdata, $N=12000$, $M=6000$, and $x$, $y$, and $a_i$ are all within the range of signed int. Translated by ChatGPT 5