#include<cstdio>
using namespace std;
const int maxn=1000005;
int n,a[maxn],ans,chk;char s[maxn];
int main(){
	scanf("%d%s",&n,s+1);
	for (int i=1;i<=n;i++) a[i]=s[i]-'0';
	if(n==1){printf("%d\n",a[1]);return 0;}
	n--;
	for (int i=1;i<=n;i++){
		a[i]-=a[i+1];
		if(a[i]<0) a[i]=-a[i];
		if(a[i]==1&&(i-1&n-1)==i-1) ans^=1;
		if(a[i]==1) chk=1;
	}
	if(ans==1){puts("1");return 0;}
	if(chk==1){puts("0");return 0;}
	for (int i=1;i<=n;i++) a[i]>>=1;
	for (int i=1;i<=n;i++)
	if(a[i]==1&&(i-1&n-1)==i-1) ans^=1;
	puts(ans?"2":"0");
	return 0;
}