Problem Statement
You are given a simple connected undirected graph $G$ with $N$ vertices and $M$ edges.
The vertices and edges of $G$ are numbered as vertex $1$, vertex $2$, $\ldots$, vertex $N$, and edge $1$, edge $2$, $\ldots$, edge $M$, respectively, and edge $i$ $(1\leq i\leq M)$ connects vertices $U_i$ and $V_i$.
You are also given distinct vertices $A,B,C$ on $G$. Determine if there is a simple path connecting vertices $A$ and $C$ via vertex $B$.
What is a simple connected undirected graph? A graph $G$ is said to be a simple connected undirected graph when $G$ is an undirected graph that is simple and connected. A graph $G$ is said to be an undirected graph when the edges of $G$ have no direction. A graph $G$ is simple when $G$ does not contain self-loops or multi-edges. A graph $G$ is connected when one can travel between all vertices of $G$ via edges.
What is a simple path via vertex $Z$? For vertices $X$ and $Y$ on a graph $G$, a simple path connecting $X$ and $Y$ is a sequence of distinct vertices $(v_1,v_2,\ldots,v_k)$ such that $v_1=X$, $v_k=Y$, and for every integer $i$ satisfying $1\leq i\leq k-1$, there is an edge on $G$ connecting vertices $v_i$ and $v_{i+1}$. A simple path $(v_1,v_2,\ldots,v_k)$ is said to be via vertex $Z$ when there is an $i$ $(2\leq i\leq k-1)$ satisfying $v_i=Z$.
Constraints
$3 \leq N \leq 2\times 10^5$$N-1\leq M\leq\min\left(\frac{N(N-1)}{2},2\times 10^5\right)$$1\leq A,B,C\leq N$$A$,$B$, and$C$are all distinct.$1\leq U_i<V_i\leq N$- The pairs
$(U_i,V_i)$are all distinct. - All input values are integers.
Input
The input is given from Standard Input in the following format:
N M
A B C
U_1 V_1
U_2 V_2
\vdots
U_M V_M
Output
If there is a simple path that satisfies the condition in the statement, print Yes; otherwise, print No.
样例
6 7
1 3 2
1 2
1 5
2 3
2 5
2 6
3 4
4 5
Yes
6 6
1 3 2
1 2
2 3
2 5
2 6
3 4
4 5
No
3 2
1 3 2
1 2
2 3
No
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