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

int main(){
    long N; cin >> N;
    vector<long> A(N); for(long i = 0; i < N; i++) cin >> A[i];
    if(N == 1){
        cout << 1 << '\n';
        return 0;
    }
    vector<long> dp(N);
    dp[0] = 1;
    dp[1] = (A[0] == A[1] ? 2 : 1);
    for(long i = 2; i < N; i++){
        dp[i] = (A[i - 1] == A[i] ? dp[i - 1] + 1 : dp[i - 2] + 1);
    }
    cout << max(dp[N - 2], dp[N - 1]) << '\n';
}