P7140 [THUPC 2021 Preliminary] Interval Matrix Multiplication
Description
You are given a sequence $a_1, a_2, \dots, a_n$ of length $n$. There are $m$ queries. Each query gives $d, p_1, p_2$. Compute
$$ \sum_{i=0}^{d-1} \sum_{j=0}^{d-1} \sum_{k=0}^{d-1} a_{p_1+d\cdot i+j} a_{p_2 + d\cdot j + k} $$
Input Format
The first line contains an integer $n$.
The next line contains $n$ integers, representing the sequence $a$.
The next line contains an integer $m$.
The next $m$ lines each contain three integers $d, p_1, p_2$, describing one query.
Constraints: $1 \le n, m, a_i \le 2 \times {10}^5$. All values are integers within $[1,{10}^9]$. The queries guarantee that the indices of $a$ are within $[1,n]$.
Output Format
Output $m$ lines, each being the answer to the corresponding query, taken modulo $2^{32}$.
Explanation/Hint
**[Source]**
From the THUPC2021 Preliminary Round of the 2021 Tsinghua University Student Algorithm Competition and University Invitational Contest (THUPC2021).
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Translated by ChatGPT 5