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// { dg-timeout-factor 2.0 }

// -*- C++ -*-

// Copyright (C) 2005, 2006, 2009, 2011 Free Software Foundation, Inc.

//

// This file is part of the GNU ISO C++ Library.  This library is free

// software; you can redistribute it and/or modify it under the terms

// of the GNU General Public License as published by the Free Software

// Foundation; either version 3, or (at your option) any later

// version.

// This library is distributed in the hope that it will be useful, but

// WITHOUT ANY WARRANTY; without even the implied warranty of

// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

// General Public License for more details.

// You should have received a copy of the GNU General Public License

// along with this library; see the file COPYING3.  If not see

// <http://www.gnu.org/licenses/>.

// Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.

// Permission to use, copy, modify, sell, and distribute this software

// is hereby granted without fee, provided that the above copyright

// notice appears in all copies, and that both that copyright notice

// and this permission notice appear in supporting documentation. None

// of the above authors, nor IBM Haifa Research Laboratories, make any

// representation about the suitability of this software for any

// purpose. It is provided "as is" without express or implied

// warranty.

/**

 * @file hash_illegal_resize_example.cpp

 * An example of illegally externally resizing a hash-based container object.

 */

/**

 * This example shows the case where a hash-based container object is

 * resized to a value which it cannot accomodate at runtime. Illegal

 * runtime resizes cause an exception.

 */

#include <ext/pb_ds/assoc_container.hpp>

#include <ext/pb_ds/hash_policy.hpp>

#include <ext/pb_ds/exception.hpp>

#include <cassert>

// size of test containers

#ifdef _GLIBCXX_DEBUG

# define SIZE 100

# define RESIZE 20

#else

# define SIZE 1000

# define RESIZE 200

#endif

using namespace std;

using namespace __gnu_pbds;

// A simple hash functor.

// hash could serve instead of this functor, but it is not yet

// standard everywhere.

struct int_hash : public unary_function<int, size_t>

{

  inline size_t

  operator()(const int& r_i) const

  { return r_i; }

};

int main()

{

  // A probing hash table mapping ints to chars.

  typedef

    gp_hash_table<

    int,

    int,

    int_hash,

    equal_to<int>,

    // Combining function.

    direct_mod_range_hashing<>,

    // Probe function.

    quadratic_probe_fn<>,

    // Resize policy.

    hash_standard_resize_policy<

    hash_prime_size_policy,

    hash_load_check_resize_trigger<>,

    /* Allow external access to size.

     *     Without setting this to true, external resizing

     *     is not possible.

     */

    true> >

    map_t;

  map_t g;

  // Insert some elements.

  int i;

  for (i = 0; i < SIZE; ++i)

    g[i] = 2*  i;

  // Check all ok.

  assert(g.size() == SIZE);

  for (i = 0; i < SIZE; ++i)

    assert(g.find(i) != g.end() && g.find(i)->second == 2 * i);

  // Now attempt to resize the table to 200 (impossible).

  bool ex_thrown = false;

  try

    {

      g.resize(RESIZE);

    }

  catch(__gnu_pbds::resize_error& )

    {

      ex_thrown = true;

    }

  // Assert an exception was thrown. A probing table cannot contain

  // 1000 entries in less than 1000 places.

  assert(ex_thrown);

  // Irrespective of the fact that the resize was not successful, the

  // container object should still be in a valid state; the following

  // checks this.

  // Check all ok.

  assert(g.size() == SIZE);

  for (i = 0; i < SIZE; ++i)

    assert(g.find(i) != g.end() && g.find(i)->second == 2 * i);

  return 0;

}