#include <bits/stdc++.h>
using namespace std;

int main() {
  ios::sync_with_stdio(false);

  int N;
  cin >> N;

  vector<int> A(N);
  for (int i = 0; i < N; ++i) {
    cin >> A[i];
  }

  vector<vector<int>> dp(N + 1, vector<int>(2));
  dp[0][0] = 0;
  for (int i = 0; i < N; ++i) {
    dp[i + 1][0] = max(dp[i + 1][0], dp[i][0]);
    dp[i + 1][0] = max(dp[i + 1][0], dp[i][1]);
    dp[i + 1][1] = max(dp[i + 1][1], dp[i][0] + 1);
    if (i == 0 || A[i] == A[i - 1]) {
      dp[i + 1][1] = max(dp[i + 1][1], dp[i][1] + 1);
    }
  }

  cout << max(dp[N][0], dp[N][1]) << endl;

  return 0;
}