33731번 - Friendship Editing 다국어

문제

Farmer John's $N$ cows are labeled 1ドル$ to $N$ (2ドル\le N\le 16$). The friendship relationships between the cows can be modeled as an undirected graph with $M$ (0ドル\le M\le N(N-1)/2$) edges. Two cows are friends if and only if there is an edge between them in the graph.

In one operation, you can add or remove a single edge from the graph. Count the minimum number of operations required to ensure that the following property holds: If cows $a$ and $b$ are friends, then for every other cow $c,ドル at least one of $a$ and $b$ is friends with $c$.

입력

The first line contains $N$ and $M$.

The next $M$ lines each contain a pair of friends $a$ and $b$ (1ドル\le a<b\le N$). No pair of friends appears more than once.

출력

The number of edges you need to add or remove.

제한

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