[NumLock]

Код:

program Project1;

{$APPTYPE CONSOLE}

uses SysUtils;

var
  s: String;

begin
  while True do
  begin
    Write('Enter number (prefix $ for hex): ');
    Readln(s);
    if s='' then Exit;
    if s[1]='$' then
    begin
      Writeln('hex number='+s);
      Writeln('dec number='+IntToStr(StrToInt64Def(s, 0)));
    end else
    begin
      Writeln('dec number='+s);
      Writeln('hex number=$'+IntToHex(StrToInt64Def(s, 0), 16));
    end;
  end;
end.