#AT2436. Ex - Count Unlabeled Graphs
Ex - Count Unlabeled Graphs
当前没有测试数据。
Ex - Count Unlabeled Graphs
Score : $600$ points
Problem Statement
You are to generate a graph by the following procedure.
- Choose a simple undirected graph with $N$ unlabeled vertices.
- Write a positive integer at most $K$ in each vertex in the graph. Here, there must not be a positive integer at most $K$ that is not written in any vertex.
Find the number of possible graphs that can be obtained, modulo $P$. ($P$ is a prime.)
Two graphs are considered the same if and only if one can label the vertices in each graph as $v_1, v_2, \dots, v_N$ to satisfy the following conditions.
- For every $i$ such that $1 \leq i \leq N$, the numbers written in vertex $v_i$ in the two graphs are the same.
- For every $i$ and $j$ such that $1 \leq i \lt j \leq N$, there is an edge between $v_i$ and $v_j$ in one of the graphs if and only if there is an edge between $v_i$ and $v_j$ in the other graph.
Constraints
- $1 \leq K \leq N \leq 30$
- $10^8 \leq P \leq 10^9$
- $P$ is a prime.
- All values in the input are integers.
Input
The input is given from Standard Input in the following format:
Output
Print the answer.
3 1 998244353
4
The following four graphs satisfy the condition.
3 2 998244353
12
The following $12$ graphs satisfy the condition.
5 5 998244353
1024
30 15 202300013
62712469