Untitled

{$o-,r+,q+}

program Project1;

{$APPTYPE CONSOLE}

uses
  SysUtils;

var
  kol, i, z, pos: integer;
  s: string;
  find: boolean;

procedure calc(s: string; cnt, last: integer);
var
  o1, o2: string;
  k, x, y, i, err: integer;
begin
  if (cnt = kol + 1) then
    exit;
  k := -1;
  err := -1;
  if (cnt <> 1) then begin
    i := last + 1;
    while (s[i] <> '+')and (s[i] <> '-') and (i < length(s)) do
      i := i + 1;
    if (i = length(s)) then
      pos := i
    else
      pos := i - 1;
  end;
  if (cnt = 1) then begin
    for i := last to pos do
      if (s[i] = '+') or (s[i] = '-') then
        k := i;
  end else
    k := last;
  if (cnt = 1) then begin
    o1 := copy(s, 1, k - 1);
    val(o1, x, err);
  end else
    x := z;
  o2 := copy(s, k + 1, pos - k);
  val(o2, y, err);
  case s[k] of
    '+': z := x + y;
    '-': z := x - y;
  end;
  calc(s, cnt + 1, pos + 1);
end;

begin
  assign(input, 'inp.in');
  assign(output, 'outp.out');
  reset(input);
  rewrite(output);

  readln(s);
  kol := 0;
  z := 0;
  pos := length(s);
  find := false;
  for i := 1 to length(s) do begin
    if (s[i] = '+') or (s[i] = '-') then
      kol := kol + 1;
    if (kol = 2) and (not find) then begin
      pos := i - 1;
      find := true;
    end;
  end;

  calc(s, 1, 1);

  write(z);

  close(input);
  close(output);
end.