#include <string>
#include <cstdio>
#include <iostream>
using namespace std;

int main() {
    int d;
    cin >> d;
    string s;
    for (int i = 1; i < 100; ++i) {
        int t = i;
        string a = to_string(t);
        s += a;
    }
    
    cout << s[d-1] << endl;
}