import java.util.*;

public class Main {

    public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner(System.in);
        int d = sc.nextInt();
        final int MAX = 100;
        StringBuilder sb = new StringBuilder();
        int num = 1;
        while(true) {
            sb.append(num);
            if(sb.length() > MAX) break; 
            num++;
        }
        String s = sb.toString();
        System.out.println(s.charAt(d-1));
    }
}