Command of the Mayor#41
To ensure victory in the elections, the mayor decided to form a team from among his acquaintances such that every member is a friend of every other member (i.e., the team must be a clique).
Given the friendship relations among all acquaintances of the mayor, construct a team of the largest possible size . If there are several possible teams, output any one of them.
The first line contains a single integer (N < 50) — the number of the mayor's acquaintances.
The second line contains an integer — the number of pairs of friends.
Each of the next lines contains two integers, the numbers of two friends, separated by a space.
Print, on the first line, a single integer — the largest possible size of the mayor's team.
On the second line, print the members of the mayor's team in increasing order by their numbers, separated by spaces.
Example 1