#include <bits/stdc++.h>

int ri() {
	int n;
	scanf("%d", &n);
	return n;
}
#define MOD 2
template<int mod>
struct ModInt{
	int x;
	ModInt():x(0){}
	ModInt(long long y):x(y>=0?y%mod:(mod-(-y)%mod)%mod){}
	ModInt &operator+=(const ModInt &p){
		if((x+=p.x)>=mod)x-=mod;
		return *this;
	}
	ModInt &operator-=(const ModInt &p){
		if((x+=mod-p.x)>=mod)x-=mod;
		return *this;
	}
	ModInt &operator*=(const ModInt &p){
		x=(int)(1LL*x*p.x%mod);
		return *this;
	}
	ModInt &operator/=(const ModInt &p){
		*this*=p.inverse();
		return *this;
	}
	ModInt &operator^=(long long p){
		ModInt res = 1;
		for (; p; p >>= 1) {
			if (p & 1) res *= *this;
			*this *= *this;
		}
		return *this = res;
	}
	ModInt operator-()const{return ModInt(-x);}
	ModInt operator+(const ModInt &p)const{return ModInt(*this)+=p;}
	ModInt operator-(const ModInt &p)const{return ModInt(*this)-=p;}
	ModInt operator*(const ModInt &p)const{return ModInt(*this)*=p;}
	ModInt operator/(const ModInt &p)const{return ModInt(*this)/=p;}
	ModInt operator^(long long p)const{return ModInt(*this)^=p;}
	bool operator==(const ModInt &p)const{return x==p.x;}
	bool operator!=(const ModInt &p)const{return x!=p.x;}
	explicit operator int() const { return x; }						   // added by QCFium
	ModInt operator=(const int p) {x = p; return ModInt(*this);} // added by QCFium
	ModInt inverse()const{
		int a=x,b=mod,u=1,v=0,t;
		while(b>0){
			t=a/b;
			a-=t*b;
			std::swap(a,b);
			u-=t*v;
			std::swap(u,v);
		}
		return ModInt(u);
	}
	friend std::ostream &operator<<(std::ostream &os,const ModInt<mod> &p){
		return os<<p.x;
	}
	friend std::istream &operator>>(std::istream &is,ModInt<mod> &a){
		long long x;
		is>>x;
		a=ModInt<mod>(x);
		return (is);
	}
};
typedef ModInt<MOD> mint;

struct MComb {
	std::vector<mint> fact;
	std::vector<mint> inversed;
	MComb(int n) { // O(n+log(mod))
		fact = std::vector<mint>(n+1,1);
		for (int i = 1; i <= n; i++) fact[i] = fact[i-1]*mint(i);
		inversed = std::vector<mint>(n+1);
		inversed[n] = fact[n] ^ (MOD-2);
		for (int i = n - 1; i >= 0; i--) inversed[i]=inversed[i+1]*mint(i+1);
	}
	mint ncr(int n, int r) {
		return (fact[n] * inversed[r] * inversed[n-r]);
	}
	mint npr(int n, int r) {
		return (fact[n] * inversed[n-r]);
	}
	mint nhr(int n, int r) {
		assert(n+r-1 < (int)fact.size());
		return ncr(n+r-1, r);
	}
};
std::vector<int> ncr_all(int n) {
	std::vector<int> res{1};
	int beki2 = 0;
	for (int i = 1; i <= n; i++) {
		int a = n - i + 1;
		int b = i;
		while (a % 2 == 0) beki2++, a /= 2;
		while (b % 2 == 0) beki2--, b /= 2;
		res.push_back(!beki2);
	}
	return res;
}

void solve(int n, int *a) {
	if (n == 1) {
		printf("%d\n", a[0]);
		return;
	}
	MComb com(n + 1);
	if (std::count(a, a + n, 1) == n) {
		puts("0");
	} else if (std::count(a, a + n, 1)) {
		for (int i = 0; i < n; i++) a[i] %= 2;
		int res = 0;
		auto b = ncr_all(n - 1);
		for (int i = 0; i < n; i++) if (b[i]) res ^= a[i];
		printf("%d\n", res);
	} else {
		int res = 0;
		auto b = ncr_all(n - 1);
		for (int i = 0; i < n; i++) if (b[i]) res ^= a[i];
		printf("%d\n", res);
	}
}
int main() {
	int n = ri();
	std::string s;
	std::cin >> s;
	int a[n - 1];
	for (int i = 0; i + 1 < n; i++) a[i] = std::abs(s[i] - s[i + 1]);
	solve(n - 1, a);
	return 0;
}




Measured memory_bytes: 19580