#include <iostream>
#include <bits/stdc++.h>
using ll = long long;
using namespace std;

int main()
{
    ll n; cin >> n;
    vector<ll> v(n);
    for (int i = 0; i < n; i++){
        cin >> v[i];
    }
    ll szam = 0;
    ll maxsize = 0;
    ll cursize = 1;
    for (int i = 1; i < n; i++){
        if (v[i] == v[i-1] && cursize >= 3){
            szam++; cursize = 1;
        }
        else {
            cursize++;
        }
        if (maxsize < cursize) maxsize = cursize;
    }
    cout << szam << "\n";
    if (szam == 0) cout << -1;
    else cout << maxsize;
    return 0;
}