program ural1027;
{$APPTYPE CONSOLE}

var
  t:array[1..10000] of Char;
  n:Longint;

procedure Init;
  begin
    n:=0;
    while not Eof do
      begin
        while not Eoln do
          begin
            Inc(n);
            Read(t[n]);
          end;
        Readln;
     {   if n=8 then Exit;   }
      end;
  end;

function Check:Boolean;
  var
    i,left:Longint;
    com,kh:Boolean;
  begin
    Check:=False;
    i:=1;left:=0;com:=False;kh:=False;
    while i<=n do
      begin
        if com then
          begin
            if t[i]='*' then
              begin
                if i=n then Exit;
                if t[i+1]=')' then
                  begin
                    com:=False;
                    Inc(i,2);
                    Continue;
                  end;
              end;
            Inc(i);
            Continue;
          end;
        if t[i]='(' then
          begin
            if i=n then Exit;
            if t[i+1]='*' then
              begin
                com:=True;
                Inc(i,2);
                Continue;
              end;
            Inc(left);
            Inc(i);
            Continue;
          end;
        if t[i]=')' then
          begin
            Dec(left);
            if left<0 then Exit;
            if left=0 then kh:=False;
            Inc(i);
            Continue;
          end;
        if kh and (Pos(t[i],'0123456789+-*/=')=0) then Exit;
        Inc(i);
      end;
    Check:=(not com) and (not kh);
  end;
begin
  Init;
  if Check then Writeln('YES') else Writeln('NO');
 { Readln;  }
e