priority_queue_erase_if.cc   [plain text]


// -*- C++ -*-

// Copyright (C) 2005, 2006 Free Software Foundation, Inc.
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// Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.

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/**
 * @file priority_queue_erase_if.cpp
 * Example showing how to conditionally erase values from a priority queue.
 */

/**
 * This example shows how to erase from a priority queue using erase_if.
 */

#include <functional>
#include <iostream>
#include <cassert>
#include <ext/pb_ds/priority_queue.hpp>

using namespace std;
using namespace pb_ds;
using namespace pb_ds;

int
main()
{
  pb_ds::priority_queue<int> p;

  // First we insert some values into the container.
  for (int i = 0; i < 1000; ++i)
    p.push(i);

  assert(p.top() == 999);

  // Now we erase all values that satisfy some predicate, in this case
  // one that returns true for all those larger than 500.
  p.erase_if(bind1st(less<int>(), 500));

  // The largest value should be now 500.
  assert(p.top() == 500);
}