P11037 [MX-X3-T4] "RiOI-4" Attending Class
Background
Original problem link: 。
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One day, Little M got up in the dorm at $6:53$, and the morning self-study starts at $7:00$。
Description
Given positive integers $n, q$ and $n$ intervals $[l_i, r_i]$。
There are $q$ queries. In each query, an integer $x$ is given. Choose an integer $a_i$ in each interval ($l_i \leq a_i \leq r_i$), so that the sum of all chosen integers equals $x$, and the variance of the chosen sequence $a$ is minimized. Output the minimum variance modulo $998\,244\,353$. It is guaranteed that there is at least one valid selection.
For the definition of variance, refer to this [Luogu paste](https://www.luogu.com.cn/paste/dpptrubn). For taking a rational number modulo, refer to [[Template] Rational Modulo](https://www.luogu.com.cn/problem/P2613)。
Input Format
The first line contains two positive integers $n, q$。
The next $n$ lines each contain two natural numbers $l_i, r_i$。
The last $q$ lines each contain an integer $x$, representing one query. It is guaranteed that there exists at least one valid selection。
Output Format
Output $q$ lines, each containing one integer: the minimum variance modulo $998\,244\,353$。
Explanation/Hint
**Sample Explanation #1**
For query 1, a selection with minimum variance is ${1,2,3}$. The minimum variance is $\frac{2}{3}$. Since $665\,496\,236 \times 3 \equiv 2 \pmod{998\,244\,353}$, output $665\,496\,236$。
For query 2, a selection with minimum variance is ${3,3,3}$. The minimum variance is $0$. Since $0 \times 1 \equiv 0 \pmod{998\,244\,353}$, output $0$。
For query 3, a selection with minimum variance is ${3,3,5}$. The minimum variance is $\frac{8}{9}$. Since $554\,580\,197 \times 9 \equiv 8 \pmod{998\,244\,353}$, output $554\,580\,197$。
**Constraints**
**This problem uses bundled testdata.**
|Subtask|Score|$n$|$q$|Special Property|
|:-:|:-:|:-:|:-:|:-:|
|$1$|$9$|$\le 5$|$\le 5$|$r_i \le 5$|
|$2$|$13$|$\le 2\times 10^3$|$\le 2\times 10^3$|$r_i \le 2\times 10^3$|
|$3$|$16$|$\le 10^6$|$= 1$||
|$4$|$25$|$\le 10^5$|$\le 10^5$|$r_i \le 10^5$|
|$5$|$37$|$\le 10^6$|$\le 10^6$||
For all testdata, $1 \leq n, q \leq 10^6$, $0 \leq l_i \leq r_i \leq 10^6$. For each $x$, it is guaranteed that there exists a valid selection.
Translated by ChatGPT 5