AtCoder Regular Contest 197 (Div. 2)
D
Ancestor Relation
AtCoder
⌀ 2062
原题
← CE →
翻译中…

Problem Statement

翻译中…

You are given an $N\times N$ matrix $A = (A_{i,j})$ ($1\le i,j\le N$) whose entries are $0$ or $1$.

翻译中…

Find, modulo $998244353$, the number of trees $G$ on $N$ vertices numbered $1$ to $N$ that satisfy the following condition.

翻译中…
  • $A_{i,j}=1$ if and only if at least one of the following holds:
  • When $G$ is rooted at vertex $1$, Vertex $j$ is an ancestor of vertex $i$. That is, vertex $j$ lies on the unique path in $G$ between vertices $1$ and $i$.
    • When $G$ is rooted at vertex $1$, Vertex $i$ is an ancestor of vertex $j$. That is, vertex $i$ lies on the unique path in $G$ between vertices $1$ and $j$.
翻译中…

Here, the endpoints of a path are considered to be on that path. Note that $G$ being a tree guarantees uniqueness of the path between any two vertices.

翻译中…

There are $T$ test cases; solve each one.

翻译中…

Constraints

翻译中…
  • $1\leq T\leq 10^5$
  • $2\leq N\leq 400$
  • $A_{i,j}\in \lbrace 0,1\rbrace$ $(1\leq i,j\leq N)$
  • $A_{i,i}=1$ $(1\leq i\leq N)$
  • $A_{i,j}=A_{j,i}$ $(1\leq i,j\leq N)$
  • The sum of $N^2$ over all test cases is at most $400^2$.
翻译中…

Input

翻译中…

The input is given from Standard Input in the following format:

翻译中…

T
\text{case}_1
\vdots
\text{case}_T

翻译中…

Each case is given in the following format:

翻译中…

N
A_{1,1} \cdots A_{1,N}
\vdots
A_{N,1} \cdots A_{N,N}

翻译中…

Output

翻译中…

Print $T$ lines. The $i$-th line should contain the number, modulo $998244353$, of trees $G$ satisfying the conditions for the $i$-th test case.

翻译中…

样例

Input #1
5
3
1 1 1
1 1 0
1 0 1
3
1 1 1
1 1 1
1 1 1
3
1 0 0
0 1 0
0 0 1
3
1 0 1
0 1 1
1 1 1
7
1 1 1 1 1 1 1
1 1 0 1 0 1 1
1 0 1 1 1 1 0
1 1 1 1 1 1 1
1 0 1 1 1 1 0
1 1 1 1 1 1 1
1 1 0 1 0 1 1
Output #1
1
2
0
0
8
In the first test case, the following one tree $G$ satisfies the condition: ![image](https://img.atcoder.jp/arc197/047f79d01c371fe5f47850c631892671.png) In the second test case, the following two trees $G$ satisfy the condition: ![image](https://img.atcoder.jp/arc197/ff998867883faff858791a57f8497f6d.png)
题目信息
题号
arc197_d
时间限制
2 s
内存限制
1024 MB

题面与样例版权归 AtCoder 及出题人所有;中文翻译由 AI 生成(CI 管线),如有出入请以原文为准。