N = gets.to_i
G = Hash.new { |h, k| h[k] = [] }

(N - 1).times do
  u, v = gets.split.map(&:to_i)

  G[u] << v
  G[v] << u
end

def bfs(v, visited)
  queue = [v]

  until queue.empty?
    v = queue.shift
    visited[v] = true

    G[v].each do |u|
      next if visited[u]

      queue << u
    end
  end
end

visited = Hash.new(false)
cnt = 0

N.times do |i|
  next if visited[i]

  cnt += 1
  bfs(i, visited)
end

if cnt >= 3
  puts 'Alice'
elsif cnt == 1
  puts 'Bob'
else
  c = (0...N).count { |v| G[v].size == 2 }

  if c == N - 1
    puts 'Bob'
  else
    puts 'Alice'
  end
end