A single integer: N There are n - 1 lines , Each line contains two space-separated integers that describe a pipe's connectivity: Ai and Bi
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A single integer: N There are n - 1 lines , Each line contains two space-separated integers that describe a pipe's connectivity: Ai and Bi
Integers, one per line and in ascending order, each denoting a possible node at which to install the chocolate inserter.
9 1 4 3 5 2 4 5 6 6 7 7 8 4 6 7 9
6 7