#include<bits/stdc++.h>
using namespace  std;
int a,b,ans; 
string s;
string _10to2(int n)
{
    s="";
    while(n)
    {
        s=char(n%2+'0')+s;
        n/=2;
    }
}
int  main( ) 
{
    cin>>a>>b;
    for (int i=a;i<=b;i++)
    {
        int it=i;
        string a=_10to2(it);
        int x=a.find("101");
        int y=a.find("010");
        if (x==-1 && y==-1)
            ans++;
    }
    cout<<ans;
    return 0;   
}