program z16_42;
var s:string;
rez,i,x,k:integer;
begin
write('aaaaeoa no?ieo');
readln(s);
val(s[1],rez,k);
i:=2;
while i<=length(s) do begin
val(s[i+1],x,k);
if s[i]='-' then rez:=rez-x
else rez:=rez+x;
i:=i+2;
end;
writeln(rez);
END.