/* winners never quit and quitters never win.
      #swap                                 */
      
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp> 
using namespace std;
using namespace __gnu_pbds;
#pragma GCC optimize ("-O3")
using ll = long long;
using ld = long double;
const ll mod = 1000000007;
const ll inf = 1000000000000000000;
const ll rk = 256;
const ld PI = 3.141592653589793;

typedef tree<
int,
null_type,
less<int>,
rb_tree_tag,
tree_order_statistics_node_update>
ordered_set;

template <typename T>
void make_unique(vector<T>& vec) {
  sort(all(vec));
  vec.erase(unique(all(vec)), vec.end());
}

#define endl '\n'
#define pb push_back
#define mp make_pair
#define vc vector
#define fs first
#define sec second
#define pql priority_queue<ll>
#define pqh priority_queue<ll,vc<ll>,greater<ll>>
#define lb lower_bound
#define ub upper_bound
#define pll pair<ll,ll> 
#define pls pair<ll,string>
#define psl pair<string,ll>
#define plc pair<ll,char>
#define pcl pair<char,ll>
#define pss pair<string,string>
#define all(x) (x).begin(), (x).end()
#define tol(s) transform(s.begin(),s.end(),s.begin(),::tolower);
#define tou(s) transform(s.begin(),s.end(),s.begin(),::toupper);
#define printclock cerr<<"Time : "<<1000*(ld)clock()/(ld)CLOCKS_PER_SEC<<"ms\n";

#define error(args...) { string _s = #args; replace(_s.begin(), _s.end(), ',', ' '); stringstream _ss(_s); istream_iterator<string> _it(_ss); err(_it, args); }

void err(istream_iterator<string> it) {}
template<typename T, typename... Args>
void err(istream_iterator<string> it, T a, Args... args) {
	cerr << *it << " = " << a << endl;
	err(++it, args...);
}

#define rep(i, begin, end) for (__typeof(end) i = (begin) - ((begin) > (end)); i != (end) - ((begin) > (end)); i += 1 - 2 * ((begin) > (end)))
#define T ll t=0;cin>>t;for(ll test=0;test<t;test++)

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());


ll nxt() {
    ll TemporaryVariable;
    cin >> TemporaryVariable;
    return TemporaryVariable;
}

struct custom_hash {
    static uint64_t splitmix64(uint64_t x) {
        // http://xorshift.di.unimi.it/splitmix64.c
        x += 0x9e3779b97f4a7c15;
        x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9;
        x = (x ^ (x >> 27)) * 0x94d049bb133111eb;
        return x ^ (x >> 31);
    }

    size_t operator()(uint64_t x) const {
        static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();
        return splitmix64(x + FIXED_RANDOM);
    }
};

 
int32_t main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);cout.tie(0);
	//isprime();
	//coeff();
	/*freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);*/
    ll n=nxt();
    string s;
    cin>>s;
    string s1="110";
    ll ans=0;
    rep(a,0,3)
    {
        bool flag=true;
        rep(b,a,a+n)
        {
            if(s1[b%3]!=s[b-a])
                flag=false;
        }
        if(flag)
        {
            ll tot=(a+n+2)/3;
            ans+=10000000000-tot+1;
        }
    }
    cout<<ans<<endl;
	printclock;
	return 0;
}
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
const ll mod = 1000000007;

int main() {
    int n;
    cin >> n;
    string t;
    cin >> t;
    if (t == "0") {
        cout << 10000000000 << endl;
        return 0;
    }
    if (t == "1") {
        cout << 20000000000 << endl;
        return 0;
    }
    if (t == "10") {
        cout << 10000000000 << endl;
        return 0;
    }
    if (t == "01") {
        cout << 9999999999 << endl;
        return 0;
    }
    if (t == "11") {
        cout << 10000000000 << endl;
        return 0;
    }
    ll zero = 0;
    if (t[0] == '0') {
        zero = 0;
    } else if (t[1] == '0') {
        zero = 1;
    } else if (t[2] == '0') {
        zero = 2;
    } else {
        cout << 0 << endl;
        return 0;
    }
    for (int i = 0; i < n; ++i) {
        if (i % 3 == zero && t[i] == '0') continue;
        if (i % 3 != zero && t[i] == '1') continue;
        cout << 0 << endl;
        return 0;
    }
    ll m = (n + 2 - zero + 2) / 3;
    cout << 10000000000 - m + 1 << endl;
}
