#include<iostream>
using namespace std;

int main() {
    int D = 0;
    cin >> D;
    
    int C[200];
    int p = 0;
    for(int i=1; i <= 100; i++) {
        if(i-10 < 0) {
            C[p] = i;
        } else if(i == 100) {
            C[p] = i/100;
            p++;
            C[p] = i/10%10;
            p++;
            C[p] = i%10;
        } else {
            C[p] = i/10;
            p++;
            C[p] = i%10;
        }
        p++;
    }
    
    cout << C[D-1] << endl;
}