Заполнить матрицу спиралью из центра против часовой стрелки

const
  rows = 5;
  cols = rows + 1;
 
var
  A : array[1 .. rows, 1 .. cols] of integer;
 
procedure spiral;
const
  dt : array[0 .. 3, 1 .. 2] of integer =
  ((1, 0), (0, -1), (-1, 0), (0, 1));
var
  X, Y : integer;
  curr_dt, counter, i, curr : Integer;
  twice : boolean;
begin
  X := cols div 2; Y := rows div 2 + rows mod 2;
  A[Y, X] := 1;
 
  curr_dt := 0; counter := 1; twice := true;
  curr := counter;
  for i := 2 to rows * cols do
  begin
    X := X + dt[curr_dt, 1]; Y := Y + dt[curr_dt, 2];
    A[Y, X] := i;
 
    dec(curr);
    if curr = 0 then
    begin
      twice := not twice;
      if twice then inc(counter);
      curr := counter;
 
      curr_dt := (curr_dt + 1) mod 4;
    end;
  end;
end;
 
var
  i, j : Integer;
begin
  spiral;
  for i := 1 to rows do
  begin
    for j := 1 to cols do write(A[i, j]:4);
    writeln;
  end;
end.