201535: [AtCoder]ARC153 F - Tri-Colored Paths
Memory Limit:1024 MB
Time Limit:2 S
Judge Style:Text Compare
Creator:
Submit:0
Solved:0
Description
Score : $1000$ points
Problem Statement
You are given a simple connected undirected graph $G$ with $N$ vertices and $M$ edges. The vertices are numbered $1$ to $N$, and the $i$-th edge connects vertices $A_i$ and $B_i$.
Find the number of ways to paint each edge of $G$ in color $1$, $2$, or $3$ so that the following condition is satisfied, modulo $998244353$.
- There is a simple path in $G$ that contains an edge in color $1$, an edge in color $2$, and an edge in color $3$.
What is a simple path?
A simple path is a pair of a sequence of vertices $(v_1, \ldots, v_{k+1})$ and a sequence of edges $(e_1, \ldots, e_k)$ that satisfies the following:- $i\neq j \implies v_i\neq v_j$;
- edge $e_i$ connects vertices $v_i$ and $v_{i+1}$.
Constraints
- $3 \leq N\leq 2\times 10^5$
- $3 \leq M\leq 2\times 10^5$
- $1 \leq A_i, B_i \leq N$
- The given graph is simple and connected.
Input
The input is given from Standard Input in the following format:
$N$ $M$ $A_1$ $B_1$ $\vdots$ $A_M$ $B_M$
Output
Print the number of ways to paint each edge of $G$ in color $1$, $2$, or $3$ so that the condition in question is satisfied, modulo $998244353$.
Sample Input 1
3 3 1 2 1 3 3 2
Sample Output 1
0
Any simple path in $G$ contains two or fewer edges, so there is no way to satisfy the condition.
Sample Input 2
4 6 1 2 1 3 1 4 2 3 2 4 3 4
Sample Output 2
534
Sample Input 3
6 5 1 3 4 3 5 4 4 2 1 6
Sample Output 3
144
Sample Input 4
6 7 1 2 2 3 3 1 4 5 5 6 6 4 1 6
Sample Output 4
1794