i cant understand the problem. https://codeforces.com/problemset/problem/1325/C
can someone help me please
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Solution
If you understand how MEX works, the problem is simple. The MEX of any path that doesn't contain the edge labeled 0 is 0. Find a vertex which has more than 3 edges, and mark them 0, 1, 2. Mark the remaining edges randomly. This ensures that the maximum MEX is 2.