#include<bits/stdc++.h>
using namespace std;

using Int = __int128_t;
Int abs128(Int val){return val<0?-val:val;}

ostream &operator<<(ostream &os,Int val){
  if(ostream::sentry(os)){
    __uint128_t tmp=abs128(val);
    char buf[64];
    char *d=end(buf);
    do{
      --d;
      *d=char(tmp%10+'0');
      tmp/=10;
    }while(tmp);
    if(val<0) *--d='-';
    Int len=end(buf)-d;
    if(os.rdbuf()->sputn(d,len)!=len){
      os.setstate(ios_base::badbit);
    }
  }
  return os;
}

istream &operator>>(istream &is,Int &val){
  string s;
  is>>s;
  val=0;
  for(Int i=0;i<(Int)s.size();i++)
    if(isdigit(s[i])) val=val*10+s[i]-'0';
  if(s[0]=='-') val*=-1;
  return is;
}


//INSERT ABOVE HERE
signed main(){
  Int x;
  cin>>x;
  string b="FESTIVAL";
  using P = pair<Int, Int>;
  const Int E=1<<9;
  vector<P> v(E,P(0,1));
  for(Int k=1;k<7;k++){
    Int tmp=0;
    for(Int i=0;i<(Int)v.size();i++){
      if(v[i].first==k-1){
	tmp+=v[i].second;
	if(__builtin_popcountll(tmp)!=1) continue;
	v.emplace(v.begin()+i+1,P(k,tmp));
	if(tmp==1) v.emplace(v.begin()+i+1,P(k,tmp));
      }
    }
    //cout<<tmp<<endl;
    for(Int i=2;i<E;i++) v.push_back(P(k,tmp));
  }
  Int tmp=0;
  for(Int i=0;i<(Int)v.size();i++){
    if(v[i].first==6){
      tmp+=v[i].second;
      if(__builtin_popcountll(tmp)!=1) continue;
      //cout<<i<<" "<<tmp<<endl;
      if(x&tmp){
	v.emplace(v.begin()+i+1,P(7,tmp));
	x^=tmp;
      }
    }
  }
  //cout<<x<<endl;
  string s;
  for(Int i=0;i<(Int)v.size();i++)
    s.push_back(b[v[i].first]);
  cout<<s<<endl;
  return 0;
}
