#include <cstdio>
#include <cstring>
#include <string>
#include <iostream>
#include <cmath>
#include <bitset>
#include <vector>
#include <map>
#include <set>
#include <queue>
#include <deque>
#include <algorithm>
#include <unordered_map>
#include <unordered_set>
#include <random>
using namespace std;
typedef long long int ll;
typedef pair<int, int> P;
int main()
{
	string s;
	for(char c='0'; c<='9'; c++) s+=c;
	for(char c1='1'; c1<='5'; c1++){
		for(char c2='0'; c2<='9'; c2++){
			s+=c1; s+=c2;
		}
	}
	int d; cin>>d;
	cout<<s[d]<<endl;
	return 0;
}