#include<iostream>
#include<algorithm>
#include <vector>
#include<cmath>
using namespace std;
int main() {
	int D;
	cin >> D;
	const string A = "123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960";
	cout << A.at(D) << endl;
}