#include <iostream>
#include <vector>
#include <string>

typedef unsigned long long ll;
using namespace std;


ll cnt(ll num){
  ll res = 0;
  ll cnt = 0;
  ll p = 10;
  ll keep = 0;
  ll k = 1;//桁
  while(p < num){
	ll tmp = (p - 1)/3 + (p - 1)/5 - (p - 1)/15;//けさないとあかん値の量
	res -= (tmp - keep)*k;//ひかなあかんりょう
	res += (p - p/10)*k;//たさなあかん
	keep = tmp;
	p *= 10;
	k++;
  }
  ll tmp = num/3 + num/5;
  res -= (tmp - num/15 - keep)*k;
  res += (num - (p/10 - 1))*k;
  res += tmp*4;
  return res;
}
pair<ll,ll> bs(ll num){
  ll l,r;
  l = 0, r = num;
  while(l+1 < r){
	ll m = (l + r)/2;

	if(cnt(m) >= num){
	  r = m;
	}
	else if(cnt(m) < num){
	  l = m;
	}
  }
 
  return pair<ll,ll>(l,cnt(l));
}
int main(){
  ll n;
  cin >> n;
  pair<ll,ll> res = bs(n);
  string str = "";
  ll cnt = 1;
  while(str.size() <= 30){
	string tmp;
	if((res.first + cnt)%3 == 0 &&  (res.first + cnt)%5 == 0){
	  str.append("FizzBuzz");	  
	}else if((res.first + cnt)%5 == 0){
	  str.append("Buzz");	  
	}else if((res.first + cnt)%3 == 0){
	  str.append("Fizz");	  	  
	}else{
	  str.append(to_string(res.first + cnt));
	}
	cnt++;
  }
  
  for(ll i = n - res.second - 1;i < n - res.second - 1 + 20;i++){
	cout << str[i];
  }
  cout << endl;
   
  return 0;
}