#include<bits/stdc++.h>
#define mod 1000000007
#define modc 998244353
using namespace std;
typedef long long ll;
ll compute(string &s)
{
	ll prod = 1;
	ll sum = 0;
	int i,j;
	reverse(s.begin(),s.end());
	for(i=0;i<s.length();i++)
	{
		sum+=(s[i]-'0')*prod;
		sum%=mod;
		prod*=2;
		prod%=mod;
	}
	reverse(s.begin(),s.end());
	return sum;
}
void solve()
{
	int n,i,j;
	ll prod = 1;
	ll sum = 0;
	cin >> n;
	string a,b,c,d;
	cin >> a;
	if(a[n-1]=='1')
	{
	for(i=0;i<n;i++)
		if(a[i] == '0')
			break;
	if(i==n)
	{
		cout << compute(a) << endl;
		return;
	}
	b = a.substr(0,i+1);
	c = a.substr(i+1,n-i-1);
	a = c+b;
	}
	int index[n] = {0};
	for(i=0;i<n;i++)
	{
		sum = 0;
		if(a[i] == '1')
		{
			sum++;
			j = i+1;
			while(a[j]=='1'&& j<n)
			{
				sum++;
				j++;
			}
			index[i] = sum;
			i = j-1;
		}
	}
	int maxx = *max_element(index,index+n);
	int ayush[n];
	int gupta = 0;
	for(i=0;i<n;i++)
	{
		if(index[i] == maxx)
			ayush[gupta++] = i;
	}
	string max_str;
	max_str = a;
	for(i=0;i<gupta;i++)
	{
		b = a.substr(0,ayush[i]);
		c = a.substr(ayush[i],n-ayush[i]);
		b = c+b;
		if(b>max_str)
			max_str = b;
	}
	cout << compute(max_str) << endl;
}
int main()
{
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	cout.tie(NULL);
	int t = 1;
//	cin >> t;
	while(t--)
		solve();
}