const fi='cfibo.inp';
fo='cfibo.out';
maxn=round(1e8);
var m,n,d:qword;
i:longint;
a: array [0..maxn] of int64;
b: array [0..maxn] of boolean;
procedure ganfibo;
begin
fillchar(b,sizeof(d),false);
a[0]:=0;
a[1]:=1;
for i:= 2 to n do a[i]:=a[i-1]+a[i-2];
for i:=0 to n do
b[a[i]]:=true;
end;
begin
assign(input,fi);
reset(input);
read(m,n);
close(input);
ganfibo;
for i:=m to n do
if b[i] then inc(d);
assign(output,fo);
rewrite(output);
write(d);
close(output);
end.