There are at most 100 testcases,and there are no more 5 testcases with $n \geq 10$.
For each test case, the first line contains two integers $n, m\ (1 \leq n \leq 16, n \leq m \leq \frac{n(n-1)}{2})$.
Then $m$ lines follows. Each of them contains two integers $u_i,v_i$, meaning that there is an edge between $u_i$ and $v_i$. It is guaranteed that the graph doesn't contain self loops or multiple edges.