if !ENV['RUBY_THREAD_VM_STACK_SIZE']
  exec({'RUBY_THREAD_VM_STACK_SIZE'=>'10000000'}, '/usr/bin/ruby', $0)
else
  N = gets.to_i
  E = Array.new(N + 1) { [] }

  (N - 1).times do
    u, v = gets.split.map(&:to_i)
    E[u] << v
    E[v] << u
  end

  used = Array.new(N + 1, false)

  def dfs(u, parent, used)
    has_child = false

    E[u].each do |v|
      next if v == parent

      dfs(v, u, used)
      has_child = true if used[v]
    end

    used[u] = true if not has_child
  end

  dfs(1, -1, used)

  puts used.count(true)
end