#include "bits/stdc++.h"
#define REP(i, n) for(int i = 0; i < int(n); i++)
#define FOR(i,n,m) for(int i = int(n); i < int(m); i++)
using namespace std;
typedef long long ll;
const int MOD = 1e9 + 7;
const int INF = 1e9 + 6;
const ll LLINF = 1e18 + 1;

int main() {
    int n; cin >> n;
    vector<int> a(n);
    REP(i, n) cin >> a[i];
    // dp[i][j] : j(unused : used)
    vector<vector<int>> dp(n+1, vector<int>(2, 0));
    REP(i, n) {
        dp[i+1][0] = max(dp[i][0], dp[i][1]);
        if (i > 0 && a[i] == a[i - 1]) {
            dp[i+1][1] = dp[i][1] + 1;
        }
        dp[i + 1][1] = max(dp[i + 1][1], dp[i][0] + 1);
    }
    cout << max(dp[n][1], dp[n][0]) << endl;
    return 0;
}