# frozen_string_literal: true


# union find
class UnionFind
  attr_reader :size

  def initialize(n)
    @parents = Array.new(n) { |i| i }
    @ranks = Array.new(n) { 0 }
    @size = Array.new(n) { 1 }
  end

  def root(x)
    if @parents[x] == x
      x
    else
      @parents[x] = root(@parents[x])
    end
  end

  def unite(x, y)
    root_x = root(x)
    root_y = root(y)
    return if root_x == root_y

    if @ranks[root_x] < @ranks[root_y]
      @parents[root_x] = root_y
      @size[root_y] += @size[root_x]
      @size[root_x] = 0
    else
      @parents[root_y] = root_x
      @size[root_x] += @size[root_y]
      @size[root_y] = 0
      @ranks[root_x] += 1 if @ranks[root_x] == @ranks[root_y]
    end
  end

  def same?(x, y)
    root(x) == root(y)
  end
end

n, m = gets.split.map(&:to_i)
ab = m.times.map { gets.split.map(&:to_i) }

u = UnionFind.new(n)

ab.each do |e|
  u.unite(e[0] - 1, e[1] - 1)
end

puts u.size.max
