更新Knuth、Morris、Pratt算法以使用unicode

Question

我有一些旧的代码(由别人写的)，我需要修复它们，以便在Delphi10.1中使用Unicode字符串。编辑:我已经将我的问题缩小到以下范围:下面的代码使用unicode字符串失败。有什么建议吗？

//global variable:  
var
  UpCaseLookup : array[ 1..255 ] of char; 


// ---- Knuth, Morris, Pratt:
type
    failure  = array[1..255] of word;

procedure PrepareUpcaseLookup;
var
  S : string; //was shortstring;
  i : integer;
begin
  for i := 1 to 255 do
  begin
    S := ToUpper( chr(i) ); //was AnsiUpperCase
    UpCaseLookup[i] := S[1]
  end
end;

Answer 1

  function PosKnuthMorrisPratt(Pattern, Text: string): Integer;
  var
    Prefix: array of Integer;
    i, k: Integer;
  begin
    Result := 0;
    if (Pattern = '') or (Text = '') then
      Exit;

    Pattern := UpperCase(Pattern); // case-insensitive
    Text := UpperCase(Text);

    // Buld prefix function array
    SetLength(Prefix, Length(Pattern) + 1);
    Prefix[1] := 0;
    k := 0;
    for i := 2 to Length(Pattern) do begin
      while (k > 0) and (Pattern[k + 1] <> Pattern[i]) do
        k := Prefix[k];
      if Pattern[k + 1] = Pattern[i] then
        Inc(k);
      Prefix[i] := k;
    end;

    k := 0;
    for i := 1 to Length(Text) do begin
      while (k > 0) and (Pattern[k + 1] <> Text[i]) do
        k := Prefix[k];
      if Pattern[k + 1] = Text[i] then
        Inc(k);
      if k = Length(Pattern) then
        Exit(i + 1 - Length(Pattern));
    end;
  end;

begin
  Memo1.Lines.Add(IntToStr(PosKnuthMorrisPratt('abaBc', 'ggabagabAbccsab')));
  Memo1.Lines.Add(IntToStr(PosKnuthMorrisPratt('ab', 'ggagbc')));