N=gets.to_i
A=gets.split.map(&:to_i)

dp=Array.new(N+1){Array.new(2,0)} #not zunda,zunda
dp[0][0]=0
N.times do |i|
  dp[i+1][0]=dp[i].max
  if i!=0 && A[i]!=A[i-1]
    dp[i+1][1]=dp[i][0]+1
  else
    dp[i+1][1]=dp[i].max+1
  end
end

puts dp[N].max