Data commit

Task/Dutch-national-flag-problem/Delphi/dutch-national-flag-problem.delphi

@@ -0,0 +1,50 @@
+const TestOrder: array [0..11] of string =
+   ('Blue','Blue','White','Blue','White','Blue',
+    'Red','White','White','Blue','White','Red');
+
+
+procedure DoDutchFlag(Memo: TMemo; Order: array of string);
+{Solve dutch flag color order using TStringList component}
+{Encode colors "Red", "White" and "Blue" to "1", "2", and "3" }
+{This allows them to be sorted in the TString List}
+var I: integer;
+var SL: TStringList;
+var S2: string;
+
+	function DecodeList(SL: TStringList): string;
+	{Convert encoded colors 1, 2 and 3 to Red, White and Blue}
+	var I: integer;
+	begin
+	Result:='';
+	for I:=0 to SL.Count-1 do
+		begin
+		if I>0 then Result:=Result+',';
+		if SL[I]='1' then Result:=Result+'Red'
+		else if SL[I]='2' then Result:=Result+'White'
+		else Result:=Result+'Blue'
+		end;
+	end;
+
+begin
+SL:=TStringList.Create;
+try
+{Encode colors from array of strings}
+for I:=0 to High(TestOrder) do
+	begin
+	if Order[I]='Red' then SL.Add('1')
+	else if Order[I]='White' then SL.Add('2')
+	else SL.Add('3');
+	end;
+Memo.Lines.Add('Original Order:');
+Memo.Lines.Add('['+DecodeList(SL)+']');
+SL.Sort;
+Memo.Lines.Add('Original Order:');
+Memo.Lines.Add('['+DecodeList(SL)+']');
+finally SL.Free; end;
+end;
+
+
+procedure ShowDutchFlag(Memo: TMemo);
+begin
+DoDutchFlag(Memo,TestOrder);
+end;