zählen mit buchstaben?

[scp]

Hier noch die 35er Variante mit 0 bis 9 und A bis Z (Buchstabe O weggelassen wegen Ähnlichkeit zu Zahl 0):

Delphi-Quellcode:

function IntPowerInt(ABaseNum, AExponent : Integer) : Integer;
var
  MultCount : Integer;
begin
  Result := 1;
  for MultCount := 1 to AExponent do
    Result := Result * ABaseNum;
end;

function AlphaToNum(ATNstr : String  ) : LongWord;
const
  ValidChars : set of Char = ['0'..'9', 'A'..'N', 'P'..'Z'];
var
  ACount : Integer;

  function CharNum(CNchr : Char) : Byte;
    begin
      Case Ord(UpCase(CNchr)) Of
        48..57: CharNum := Ord(UpCase(CNchr)) - 48;
        65..78: CharNum := Ord(UpCase(CNchr)) - 55;
        80..90: CharNum := Ord(UpCase(CNchr)) - 56;
      end;
    end;
begin
  AlphaToNum := 0;
  for ACount := 1 to length(ATNstr) do
    begin
      If not (UpCase(ATNstr[ACount]) in ValidChars) then
        begin
          result := 0;
          Break;
        end;
      result := result + (CharNum(ATNstr[ACount]) * IntPowerInt(35, length(ATNstr) - ACount));
    end;
end;

function NumToAlpha(NTAnum : LongWord  ) : String;
var
  NumChar  : array[0..34] Of Char;
  NumCount : Word;
begin
  for NumCount :=  0 to  9 do NumChar[NumCount] := Chr(48 + NumCount);
  for NumCount := 10 to 23 do NumChar[NumCount] := Chr(55 + NumCount);
  for NumCount := 24 to 34 do NumChar[NumCount] := Chr(56 + NumCount);

  // max 35 hoch (7-1)
  result := '';
  for NumCount := 7 downto 1 do
    If (NTAnum < IntPowerInt(35, NumCount)) then
      begin
        result := result + NumChar[NTAnum div IntPowerInt(35, NumCount-1)];
        NTAnum := NTAnum mod IntPowerInt(35, NumCount-1);
      end;

end;

Delphi-Quellcode:

s1 := 'AZGE';
s2 := 'X45B';
s3 := NumToAlpha(AlphaToNum(s1) + AlphaToNum(s2));