Шифрование текста в RSA

function Bit(Value, n: Integer): Boolean;
asm
   bt eax, edx
   setc al
   and eax, 0FFh
end;
 
function FastPower(a, b, n: integer): integer;
var i: integer;
    ai: extended;
begin
  ai := a;
  for I := Trunc(log2(b)) - 1 downto 0 do
  if Bit(b, i) then ai := Round(sqr(ai) * a) mod n else ai := Round(sqr(ai)) mod n;
  result := Round(ai);
end;
 
function Encrypt(s: string; e, n: integer): TIncodeMes;
  var I: Integer;
begin
  SetLength(result, length(s));
  for I := 0 to Length(s) - 1 do
    result[i] := FastPower(ord(s[i + 1]), e, n)
end;
 
function Decrypt(s: array of integer; e, n: integer): string;
  var i: Integer;
begin
  SetLength(Result, Length(s));
  for I := 0 to Length(s) - 1 do
    result[i + 1] := chr(FastPower(s[i], e, n))
end;
 
procedure TForm16.Button1Click(Sender: TObject);
  var i, n, e: Integer;
begin
  n := StrToIntDef(Edit3.Text, 697);
  e := StrToIntDef(Edit2.Text, 7);
  FMes := Encrypt(Memo1.Lines.Text, e, n);
  for i := 0 to High(FMes) do Memo2.Lines.Append(IntToStr(FMes[i]));
end;
 
procedure TForm16.Button2Click(Sender: TObject);
var i, n, d: integer;
 s : string;
 begin
 SetLength(FMes, Memo2.lines.count);
 for i := 0 to Memo2.Lines.Count-1 do
 Fmes[i] := StrToInt(Memo2.lines[i]);
 d := StrToIntDef(Edit1.Text, 183);
 n := StrToIntDef(Edit3.Text, 697);
 s := Decrypt(FMes,d , n);
 Memo3.Lines.Add(s)
end;