function DecChas(chas: string): string;
var
 Decchas : string;
 str : string;
 I : Integer;
 Len : integer;
begin

 str := Copy(chas, 6, 12);
 Len := Length(str);

 For I := 0 To Length(str) -1 do
 begin
  Decchas := Decchas + str[len];
  Inc(len, -1);
 end;

 str := Copy(chas, 21, Length(chas) -5);
 str := str + Copy(chas, 5, 1);

 Len := Length(str);

 For I := 0 To Length(str) -1 do
 begin
   Decchas := Decchas + str[len];
   Inc(len, -1);
 end;

 Result := Decchas;
end;