import strutils, sequtils var g: seq[seq[int]] ans = 0 proc f(i, p: int): bool = var cnt = 0 for j in g[i]: if j!=p: if not f(j, i): cnt+=1 result = cnt>0 if not result: ans+=1 proc main() = let n = stdin.readLine.parseInt g = newSeqWith(n, newSeq[int]()) for _ in 1..