Problem Statement
You are given a simple undirected graph $G$ with $N$ vertices and $M$ edges, where vertices are numbered $1$ to $N$. The $i$-th edge connects vertices $u_i$ and $v_i$.
Initially, no vertices of $G$ are colored. Alice and Bob will play a game using $G$. Alice and Bob perform the following actions in order for $t=1,\ldots,N$:
- If
$t$is odd, Alice chooses one vertex that is not yet colored and colors that vertex black. - If
$t$is even, Bob chooses one vertex that is not yet colored and colors that vertex white.
After all $N$ actions are completed, if the set of all vertices colored black is an independent set of $G$, Alice is the winner; otherwise, Bob is the winner. Output the name of the winner when both players play optimally.
You are given $T$ test cases; solve each of them.
What is an independent set A set $S$ consisting of vertices of a simple undirected graph $G$ is an independent set of $G$ if there does not exist a pair of vertices $u$ and $v$ connected by an edge such that $u\in S$ and $v\in S$.
Constraints
$1\leq T\leq 2\times 10^5$$2\leq N\leq 2\times 10^5$$0\leq M\leq 2\times 10^5$$1\leq u_i < v_i \leq N$- The given graph is a simple undirected graph.
- The sum of
$N$over all test cases is at most$2\times 10^5$. - The sum of
$M$over all test cases is at most$2\times 10^5$.
Input
The input is given from Standard Input in the following format:
T
\mathrm{case}_1
\mathrm{case}_2
\vdots
\mathrm{case}_T
Each case is given in the following format:
N M
u_1 v_1
\vdots
u_M v_M
Output
Output $T$ lines. The $i$-th line should contain the name of the winner (Alice or Bob) for the $i$-th test case when both players play optimally.
样例
3
3 2
1 2
1 3
4 2
1 2
1 3
4 6
1 2
1 3
1 4
2 3
2 4
3 4
Bob
Alice
Bob
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