function GetHeight(node: PNode): Integer;
var
  leftHeight, rightHeight: Integer;
begin
  if node = nil then
    Result := 0
  else
  begin
    leftHeight := GetHeight(node.Left);
    rightHeight := GetHeight(node.Right);
    Result := Max(leftHeight, rightHeight) + 1;
  end;
end;

function IsBalanced(node: PNode): Boolean;
var
  leftHeight, rightHeight: Integer;
begin
  if node = nil then
    Result := True
  else
  begin
    leftHeight := GetHeight(node.Left);
    rightHeight := GetHeight(node.Right);
    if Abs(leftHeight - rightHeight) <= 1 then
      Result := IsBalanced(node.Left) and IsBalanced(node.Right)
    else
      Result := False;
  end;
end;

procedure AddNode(var root: PNode; value: Integer);
begin
  if root = nil then
  begin
    New(root);
    root.Data := value;
    root.Left := nil;
    root.Right := nil;
  end
  else if value < root.Data then
    AddNode(root.Left, value)
  else
    AddNode(root.Right, value);
end;

procedure DeleteNodesToBalance(root: PNode);
var
  nodesToDelete: array of Integer;

  procedure Traverse(node: PNode);
  begin
    if node <> nil then
    begin
      if not IsBalanced(node) then
        SetLength(nodesToDelete, Length(nodesToDelete) + 1);
        nodesToDelete[High(nodesToDelete)] := node.Data;

      Traverse(node.Left);
      Traverse(node.Right);
    end;
  end;

var
  i: Integer;
begin
  Traverse(root);

  if Length(nodesToDelete) > 0 then
  begin
    WriteLn('Values to delete to balance the tree:');
    for i := 0 to High(nodesToDelete) do
      WriteLn(nodesToDelete[i]);
  end
  else
    WriteLn('The tree is already balanced.');
end;