gistfile1.pas

function m10w31(code: string): integer;
/**
 Delphi版　モジュラス１０ウエィト３のチェックデジット計算。
*/
var
  i,w,sum: integer;
begin
  w := 3;
  sum := 0;
  for i := length(code) downto 1 do
  begin
    sum := sum + strtoint(code[i]) * w;
    if w = 3 then w := 1
    else w := 3;
  end;
  Result := sum mod 10;
  if Result<>0 then Result := 10 - Result;
end;