#include<bits/stdc++.h>
#include<atcoder/all>
using namespace std;
using namespace atcoder;
typedef long long int ll;
typedef long double ld;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef vector<vvl> vvvl;
typedef vector<vvvl> vvvvl;
typedef vector<bool> vb;
typedef vector<vb> vvb;
typedef vector<vvb> vvvb;
typedef vector<vvvb> vvvvb;
typedef pair<ll,ll> pl;
typedef pair<ll,pl> ppl;
typedef pair<ll,ppl> pppl;
typedef pair<ll,pppl> pppppl;
#define rep(i,a,b) for(int i=(a);i<(b);i++)
#define rrep(i,a,b) for(int i=(b)-1;i>=(a);i--)
#define all(a) begin(a),end(a)
#define sz(a) (int)(a).size()
#define F first
#define S second
#define bs(A,x) binary_search(all(A),x)
#define lb(A,x) (ll)(lower_bound(all(A),x)-A.begin())
#define ub(A,x) (ll)(upper_bound(all(A),x)-A.begin())
#define cou(A,x) (ll)upper_bound(all(A),x)-lower_bound(all(A),x))
template<typename T>using min_priority_queue=priority_queue<T,vector<T>,greater<T>>;
template<class T>bool chmax(T&a,T b){if(a<b){a=b;return 1;}return 0;}
template<class T>bool chmin(T&a,T b){if(b<a){a=b;return 1;}return 0;}
//*
using mint=modint998244353;
const ll mod=998244353;
//*/
/*
using mint=modint1000000007;
const ll mod=1000000007;
//*/
//using mint=modint;
//*
typedef vector<mint> vm;
typedef vector<vm> vvm;
typedef vector<vvm> vvvm;
typedef vector<vvvm> vvvvm;
ostream&operator<<(ostream&os,mint a){os<<a.val();return os;}
istream&operator>>(istream&is,mint&a){int x;is>>x;a=mint(x);return is;}
//*/
template<typename T1,typename T2>ostream&operator<<(ostream&os,pair<T1,T2>p){os<<p.F<<" "<<p.S;return os;}
template<typename T1,typename T2>istream&operator>>(istream&is,pair<T1,T2>&p){is>>p.F>>p.S;return is;}
template<typename T>ostream&operator<<(ostream&os,vector<T>v){rep(i,0,sz(v))os<<v[i]<<(i+1!=sz(v)?" ":"");return os;}
template<typename T>istream&operator>>(istream&is,vector<T>&v){for(T&in:v)is>>in;return is;}
string to_hex_string(int64_t i){
  stringstream s;
  s<<uppercase<<hex<<i;
  return s.str();
}
string FizzBuzz16(int64_t i){
  if(i%15==0)return "FizzBuzz";
  else if(i%3==0)return "Fizz";
  else if(i%5==0)return "Buzz";
  else return to_hex_string(i);
}
ll length(ll N){
  //1,2,...,Nの長さ
  ll ans=0;
  for(ll l=1,d=1;l<=N;l*=16,d++){
    ll r=min(N,16*l-1);
    ll f=r/3-(l-1)/3;
    ll b=r/5-(l-1)/5;
    ll fb=r/15-(l-1)/15;
    ans+=d*(r-l+1-f-b+fb);
    ans+=f*4+b*4;
  }
  return ans;
}
ll g(ll N){
  //[1,N]までのfbの和
  ll ans=N/3+N/5;
  vl T(12);
  for(ll n=N,i=0;i<12;i++,n/=16)T[i]=n%16;
  //mod15で0,3,5,6,9,10,12でない数だけをみる，FBは何個現れる？
  vvl dp(12,vl(15)),ep(12,vl(15));
  vvl _dp(12,vl(15)),_ep(12,vl(15));
  dp[11][0]=1;
  rrep(i,0,11)rep(j,0,15)rep(k,0,16){
    ll d=(k==11||k==15);
    ll l=(16*j+k)%15;
    
    //ep->ep
    ep[i][l]+=ep[i+1][j];
    _ep[i][l]+=_ep[i+1][j]+d*ep[i+1][j];
    if(T[i]>k){
      //dp->ep
      ep[i][l]+=dp[i+1][j];
      _ep[i][l]+=_dp[i+1][j]+d*dp[i+1][j];
    }
    if(T[i]==k){
      //dp->dp
      dp[i][l]+=dp[i+1][j];
      _dp[i][l]+=_dp[i+1][j]+d*dp[i+1][j];
    }
  }
  rep(i,0,15)if(i%3&&i%5)ans+=_dp[0][i]+_ep[0][i];
  return ans;
}
ll f(ll N){
  //N文字目までのfbの和
  ll l=0,r=N+10;
  while(r-l>1){
    ll m=(l+r)/2;
    if(length(m)>N)r=m;
    else l=m;
  }
  ll q=length(l);
  string s=FizzBuzz16(l+1);
  ll ans=g(l);
  rep(i,0,N-q)if(s[i]=='F'||s[i]=='B')ans++;
  return ans;
}
int main(){
  cin.tie(0)->sync_with_stdio(0);
  cin.exceptions(cin.failbit);
  ll X,Y;cin>>X>>Y;
  cout<<f(Y)-f(X-1)<<endl;
  return 0;
}