program nfcdjcfi;
uses crt;
var e:array [1..100] of integer;
i,a,b,kolvo:integer;
begin
clrscr;
kolvo:=0;
readln(a,b);
for i:=a to b do
if e[i] mod 2 =0 then kolve:=kolvo+1;
writeln(kolvo);
readln;
end.
