class A
  def initialize
    n = gets.chomp.to_i
    m = gets.chomp.to_i

    cup = [0,0,0,0]
    cup[n] = 1

    m.times do
      p, q = gets.chomp.split(' ').map(&:to_i)

      cup[p], cup[q] = cup[q], cup[p]
    end

    puts cup.index(1)
  end
end

A.new