#include <bits/stdc++.h>

using namespace std;
using ll = long long;
using ld = long double;

const ld pi = 3.14159265358979;
const int mod = 1000000007;

int main(){
	int n;
	cin >> n;
	vector<int> a(n);
	for(int i = 0; i < n; i++){
		cin >> a[i];
	}
	vector<vector<int>> dp(n + 10 , vector<int>(2 , 0));
	dp[0][0] = 0;
	dp[0][1] = 1;
	for(int i = 1; i < n; i++){
		if(a[i] != a[i - 1]){
			dp[i][0] = max(dp[i - 1][1] , dp[i - 1][0]);
			dp[i][1] = dp[i - 1][0] + 1;
		}else{
			dp[i][1] = max(dp[i - 1][1] + 1 , dp[i - 1][0] + 1);
			dp[i][0] = max(dp[i - 1][0] , dp[i - 1][1]);
		}
	}
	cout << max(dp[n - 1][0] , dp[n - 1][1]) << endl;
	return 0;
}