Products_solved_fully

(*
 * Project: Pascal
 * User: akelix
 * Date: 20.12.18
 *)
program products;
Var
  inputFile : text;
Var
  productsNeedCount, productsHasCount: integer;
Var
  productsNeedList, productsHasList: array of integer;
Var
  productsWeDoNotHaveList: array of integer;

procedure ReadArray(inputFile: text; products: array of integer; count: integer);
begin
  for var i := 0 to count - 1 do
    Read(inputFile, products[i]);
end;

function DoNotHaveThisItem(items: array of integer; itemWeSeek: integer): boolean;
begin
  Result:=true;
  for var i:= 0 to items.Length - 1 do
    if items[i] = itemWeSeek then
    begin
      items[i] := -1;
      Result:=false;
    end;
end;

function FindMissedProducts(productsNeed: array of integer; productsHas: array of integer; weDoNotHaveThisProducts: array of integer): integer;
begin
  Result:=0;

  for var i:=0 to productsNeed.Length -1 do
    if DoNotHaveThisItem(productsHas, productsNeed[i]) then
      begin
        weDoNotHaveThisProducts[Result] := productsNeed[i];
        inc(Result);
      end;
end;


begin

  Assign(inputFile, 'input_products.txt');
  Reset(inputFile);
  Read(inputFile, productsNeedCount, productsHasCount);

  SetLength(productsNeedList, productsNeedCount);
  SetLength(productsHasList, productsHasCount);
  SetLength(productsWeDoNotHaveList, productsNeedCount);

  ReadArray(inputFile, productsNeedList, productsNeedCount);
  ReadArray(inputFile, productsHasList, productsHasCount);

  close(inputFile);

  Println('Данные прочитаны:');
  Println(productsNeedList);
  Println(productsHasList);

  var missedItemsCount: integer = FindMissedProducts(productsNeedList, productsHasList, productsWeDoNotHaveList);
  SetLength(productsWeDoNotHaveList, missedItemsCount);

  Println('Результат:');
  if missedItemsCount > 0 then
    begin
      Print('нет, этого не хватает:');
      Println(productsWeDoNotHaveList);
    end
  else
    Println('да, все есть.');

end.