Три группы студентов. Определить лучшую по средней оценке группу.

unit Unit1;
 
interface
 
uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, Grids;
 
type
  TForm1 = class(TForm)
    StringGrid1: TStringGrid;
    btn1: TButton;
    StringGrid2: TStringGrid;
    StringGrid3: TStringGrid;
    procedure btn1Click(Sender: TObject);
    procedure FormCreate(Sender: TObject);
    function Check(a:String):Real;
  private
    { Private declarations }
  public
    { Public declarations }
  end;
 
var
  Form1: TForm1;
  s1,s2,s3: Real;
  best: String;
 
implementation
 
{$R *.dfm}
 
 
procedure TForm1.FormCreate(Sender: TObject);
begin
  with StringGRid1 do
    begin
      Options := Options+[goEditing];
      Cells[0,0] := 'Gruppa 1';
      Cells[1,0] := 'Math';
      Cells[2,0] := 'Phis';
      Cells[3,0] := 'Chem';
    end;
  with StringGRid2 do
    begin
      Options := Options+[goEditing];
      Cells[0,0] := 'Gruppa 2';
      Cells[1,0] := 'Math';
      Cells[2,0] := 'Phis';
      Cells[3,0] := 'Chem';
    end;
  with StringGRid3 do
    begin
      Options := Options+[goEditing];
      Cells[0,0] := 'Gruppa 3';
      Cells[1,0] := 'Math';
      Cells[2,0] := 'Phis';
      Cells[3,0] := 'Chem';
    end;
end;
 
procedure TForm1.btn1Click(Sender: TObject);
var
  i,j: Integer;
begin
  s1 := 0; s2 := 0; s3 := 0;
  best := '';
  for i := 1 to 3 do
   for j := 1 to 21 do
    begin
      s1 := s1+Check(StringGrid1.Cells[i,j]);
      s2 := s2+Check(StringGrid2.Cells[i,j]);
      s3 := s3+Check(StringGrid3.Cells[i,j]);
    end;
  s1 := s1/60; s2 := s2/60; s3 := s3/60;
  if (s1>s2) and (s1>s3) then best := 'Gruppa 1'
  else
   begin
    if (s2>s3) then best := 'Gruppa 2';
    if (s3>s2) then  best := 'Gruppa 3';
    if (best='') then best := 'All';
   end;
  ShowMessage(best);
end;
 
function TForm1.Check(a:String):Real;
begin
  if a='' then result := 0
  else result := StrToFloat(a);
end;
 
end.