Problem I. Problem I. Delightful Formulas

时间限制 10000 ms   内存限制 256 MB

Kazari is too bored this summer holiday, she decides to play with formulas.
First of all, she comes up with two positive integers $N, K$.
She loves power, therefore she builds a sequence $a$ where $a_i = i ^ K$ $(1 \le i \le N)$.
She loves summation, therefore she calculate the partial sum of $a$ as $s$, i.e. $s_i = \sum_{j \le i} {a_j}$ $(1 \le i \le N)$.
She also loves coprimes, therefore she calculate the sum of elements in $s$ whose index $i$ is coprime to $N$, i.e. $v = \sum_{1 \le i \le N, \gcd(i, N) = 1} {s_i}$
Your task is to work out $v$. Since the answer is too large, print it modulo $998244353$.
 

输入数据

The first line of the input contains an integer $T$ denoting the number of test cases.
Each test case starts with a positive integer $K$ $(K \le 10 ^ 5, \sum{K} \le 10 ^ 6)$.
The second line contains a positive integer $m$ $(m \le 20)$, indicating the number of distinct primes of $N$.
Each of next $m$ lines contains two positive integers $p_i, a_i$ where $p_i$ is a prime $(p_i, a_i \le 10 ^ 9, p_i < p_{i + 1})$.
$$N = \prod_{i = 1} ^ {m} {p_i ^ {a_i}}$$
 

输出数据

For each test case, print an integer representing the answer modulo $998244353$.
 

样例输入

复制
2
1
2
2 1
3 1
233
1
23333 1

样例输出

复制
16
32727388

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