#include "bits/stdc++.h"
#include <random>
#define REP(i, n) for (ll i = 0; i < ll(n); ++i)
#define RREP(i, n) for (ll i = ll(n) - 1; i >= 0; --i)
#define FOR(i, m, n) for (ll i = m; i < ll(n); ++i)
#define RFOR(i, m, n) for (ll i = ll(n) - 1; i >= ll(m); --i)
#define ALL(v) (v).begin(), (v).end()
#define UNIQUE(v) v.erase(unique(ALL(v)), v.end());
#define INF 1000000001ll
#define MOD 1000000007ll
#define EPS 1e-9

constexpr int dx[8] = {1, 1, 0, -1, -1, -1, 0, 1};
constexpr int dy[8] = {0, 1, 1, 1, 0, -1, -1, -1};

using namespace std;

using ll = long long;
using vi = vector<int>;
using vl = vector<ll>;
using vvi = vector<vi>;
using vvl = vector<vl>;
using pii = pair<int, int>;
using pll = pair<ll, ll>;

template <class T> bool chmin(T &a, const T &b) {
  if (a > b) {
    a = b;
    return true;
  }
  return false;
}
template <class T> bool chmax(T &a, const T &b) {
  if (a < b) {
    a = b;
    return true;
  }
  return false;
}

#include "bits/stdc++.h"
template <int mod, bool isPrime = false> class Mint {
  using ll = long long;
  bool dirty;
  ll value;

public:
  static std::vector<Mint> fact;
  static std::vector<Mint> rfact;
  constexpr Mint() : value(0), dirty(false){};
  constexpr Mint(ll x) : value(x), dirty(true) {
    value %= mod;
    if (value < 0)
      value += mod;
  }
  constexpr Mint(const Mint &other) : value(other.value), dirty(other.dirty) {}

  ll &get() { return value; }
  ll get() const { return value; }

  constexpr Mint pow(ll n) {
    Mint ret(1), tmp(value);
    while (n) {
      if (n & 1)
        ret *= tmp;
      n >>= 1;
      tmp *= tmp;
    }
    return ret;
  }
  constexpr bool initialized() const { return dirty; }
  constexpr bool operator==(const Mint &a) const { return value == a.value; }
  constexpr bool operator!=(const Mint &a) const { return value != a.value; }
  constexpr Mint &operator=(const Mint &a) {
    value = a.value;
    dirty = true;
    return *this;
  }
  constexpr Mint &operator+=(const Mint &a) {
    if ((value += a.value) >= mod)
      value -= mod;
    dirty = true;
    return *this;
  }
  constexpr Mint &operator-=(const Mint &a) {
    if ((value += mod - a.value) >= mod)
      value -= mod;
    dirty = true;
    return *this;
  }
  constexpr Mint &operator*=(const Mint &a) {
    value = value * a.value % mod;
    dirty = true;
    return *this;
  }

  constexpr Mint &operator/=(const Mint &a) {
    initialized = true;
    return *this *= inv(a);
  }
  constexpr Mint operator+(const Mint &a) const { return Mint(*this) += a; }
  constexpr Mint operator-(const Mint &a) const { return Mint(*this) -= a; }
  constexpr Mint operator*(const Mint &a) const { return Mint(*this) *= a; }
};

template <int mod, bool isPrime>
std::ostream &operator<<(std::ostream &os, const Mint<mod, isPrime> &m) {
  os << m.get();
  return os;
}
template <int mod, bool isPrime>
std::istream &operator>>(std::istream &is, Mint<mod, isPrime> &m) {
  is >> m.get();
  return is;
}

template <int mod> constexpr Mint<mod, true> inv(const Mint<mod, true> &m) {
  long long a = m.get(), b = mod, u = 1, v = 0;
  while (b) {
    long long t = a / b;
    a -= t * b;
    std::swap(a, b);
    u -= t * v;
    std::swap(u, v);
  }
  return Mint<mod, true>(u);
}

template <int mod, bool isPrime>
constexpr Mint<mod, isPrime> operator+(long long lhs,
                                       const Mint<mod, isPrime> &a) {
  return Mint<mod, isPrime>(lhs + a.get());
}

template <int mod, bool isPrime>
constexpr Mint<mod, isPrime> operator-(long long lhs,
                                       const Mint<mod, isPrime> &a) {
  return Mint<mod, isPrime>(lhs - a.get());
}

template <int mod, bool isPrime>
constexpr Mint<mod, isPrime> operator*(long long lhs,
                                       const Mint<mod, isPrime> &a) {
  return Mint<mod, isPrime>(lhs % mod * a.get());
}

template <int mod>
constexpr Mint<mod, true> operator/(long long lhs, const Mint<mod, true> &a) {
  return Mint<mod, true>(lhs % mod * inv(a));
}

constexpr int default_mod = 2;
using mint = Mint<default_mod, true>;

int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  int n;
  cin >> n;
  vector<int> v(n);
  {
    string s;
    cin >> s;
    REP(i, n) v[i] = s[i] - '0';
  }
  auto comb = [&](int a, int b) { return (a | b) == a; };
  auto is_1 = [&](vector<int> &a) {
    mint pari = 0;
    REP(i, a.size()) pari += a[i] * comb(a.size() - 1, i);
    return pari == 1;
  };

  if (is_1(v)) {
    cout << 1 << endl;
    return 0;
  }
  vector<int> w(n - 1);
  REP(i, n - 1) w[i] = abs(v[i] - v[i + 1]);

  bool flag = true;
  REP(i, n - 1) if (w[i] == 1) flag = false;
  if (flag) {
    mint par = 0;
    REP(i, n - 1) par += (w[i] == 2) * comb(n - 2, i);
    if (par == 1) {
      cout << 2 << endl;
      return 0;
    }
  }

  cout << 0 << endl;
}


Measured memory_bytes: 8264