var a,b: integer;
begin
readln(a,b);
while (a mod 13<>0)and(a<b) do a:=a+1;
if a mod 13=0 then writeln(a) else writeln('No');
end.
var a,b: integer;
begin
readln(a,b);
while (a mod 13<>0)and(a<b) do a:=a+1;
if a mod 13=0 then writeln(a) else writeln('No');
end.