island_num = gets.to_i
bridge_num = island_num - 1
island_with_bridge = (0...island_num).inject({}) { |result, i| result[i] = 0; result }
bridge_num.times do
  islands = gets.split
  island_with_bridge[islands[0].to_i] += 1
  island_with_bridge[islands[1].to_i] += 1
end

if island_with_bridge.values.find { |v| v == 0 } && island_with_bridge.values.find { |v| v == 1 }
  puts "Alice"
else
  puts "Bob"
end