{*************************************************
**  小マス目の水平・水直方向　を調べる
**   lct:TPointの属する小ブロック内
**
**************************************************}
function TForm1.small_area_Check(lct:TPoint):boolean;
var
  i,j,x,y : integer;
  s_i,s_j : integer;
  msg : string;
begin
  x := lct.X;
  y := lct.Y;
  s_i := ( x div 3 ) * 3;
  s_j := ( y div 3 ) * 3;
  result := True;
  for i := s_i to s_i + 2  do
    for j := s_j to s_j + 2 do
      begin
        if Darray[i,j] <> 0 then
          continue;

        if DArray[x][y] in KnAry[i][j] then
          KnAry[i][j] := KnAry[i][j]
                          - [ DArray[x][y]];
        if KnAry[i,j] = [] then
          begin
            result := False;
            exit;
          end;
       end;
end;