#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <queue>
#include <set>
#include <map>
#include <cmath>
using namespace std;
typedef long long i64;
typedef long double ld;
typedef pair<i64,i64> P;
#define rep(i,s,e) for(int i = (s);i <= (e);i++)

i64 s;

i64 here(i64 from ,i64 to,i64 MOD){

	if(from % MOD != 0){
		from += MOD - (from % MOD);
	}
	{
		to -= to % MOD;
	}
	i64 cou = (to - from) / MOD + 1;
	return cou;
}

i64 c(i64 k){
	int digit = 1;
	i64 res = 0;
	{
		i64 i;
		for(i = 10;i <= k;i *= 10){
			res += (i - 1 - (i / 10) + 1) * digit;
			i64 from = i / 10;
			i64 to = i - 1;
			i64 three = here(from,to,3);
			i64 five = here(from,to,5);
			i64 both = here(from,to,15);
			res += -three * digit + three * 4 - five * digit + five * 4 + both * digit;
			digit++;
		}
		i /= 10;
		{
			res += (k - i + 1) * digit;
			i64 from = i;
			i64 to = k;
			i64 three = here(from,to,3);
			i64 five = here(from,to,5);
			i64 both = here(from,to,15);
			res += -three * digit + three * 4 - five * digit + five * 4 + both * digit;
		}
	}
	return res;
}

i64 binary(){
	i64 ok = 1;
	i64 ng = 1e18;
	while(ng - ok > 1){
		i64 mid = (ng + ok) / 2;
		if(c(mid) <= s){
			ok = mid;
		}
		else
		{
			ng = mid;
		}
	}
	return ok;
}

int main(){
	cin >> s;
	i64 num = binary();
	i64 start = c(num - 1);
	string ans = "";
	s--;
	i64 sz = s - start + 20;
	for(i64 i = num;ans.size() < sz;i++){
		if(i % 3 == 0) ans += "Fizz";
		if(i % 5 == 0) ans += "Buzz";
		if(i % 3 != 0 && i % 5 != 0) ans += to_string(i);
	}

	cout << ans.substr(s-start, 20) << endl;;
}

