C++ Tutorial/STL Algorithms Heap/push heap

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Sort vector1 using push_heap and pop_heap

#include <iostream>
#include <cassert>
#include <algorithm>
#include <vector>
using namespace std;
int main()
{
  vector<int> vector1(5);
  for (int i = 0; i < 5; ++i)
    vector1[i] = i;
  random_shuffle(vector1.begin(), vector1.end());
  
  for (int i = 2; i <= 5; ++i)
    push_heap(vector1.begin(), vector1.begin() + i);
  
  for (int i = 5; i >= 2; --i)
    pop_heap(vector1.begin(), vector1.begin() + i);
  
  for (int i = 0; i < 5; ++i)   
    cout << vector1[i];
  return 0;
}
01234

Use push_heap to push new element into the heap

/* The following code example is taken from the book
 * "The C++ Standard Library - A Tutorial and Reference"
 * by Nicolai M. Josuttis, Addison-Wesley, 1999
 *
 * (C) Copyright Nicolai M. Josuttis 1999.
 * Permission to copy, use, modify, sell and distribute this software
 * is granted provided this copyright notice appears in all copies.
 * This software is provided "as is" without express or implied
 * warranty, and with no claim as to its suitability for any purpose.
 */

#include <iostream>
#include <vector>
#include <deque>
#include <list>
#include <set>
#include <map>
#include <string>
#include <algorithm>
#include <iterator>
#include <functional>
#include <numeric>
/* PRINT_ELEMENTS()
 * - prints optional C-string optcstr followed by
 * - all elements of the collection coll
 * - separated by spaces
 */
template <class T>
inline void PRINT_ELEMENTS (const T& coll, const char* optcstr="")
{
    typename T::const_iterator pos;
    std::cout << optcstr;
    for (pos=coll.begin(); pos!=coll.end(); ++pos) {
        std::cout << *pos << " ";
    }
    std::cout << std::endl;
}
/* INSERT_ELEMENTS (collection, first, last)
 * - fill values from first to last into the collection
 * - NOTE: NO half-open range
 */
template <class T>
inline void INSERT_ELEMENTS (T& coll, int first, int last)
{
    for (int i=first; i<=last; ++i) {
        coll.insert(coll.end(),i);
    }
}

using namespace std;
int main()
{
    vector<int> coll;
    INSERT_ELEMENTS(coll,3,7);
    INSERT_ELEMENTS(coll,5,9);
    INSERT_ELEMENTS(coll,1,4);
    PRINT_ELEMENTS (coll, "on entry:           ");
    // convert collection into a heap
    make_heap (coll.begin(), coll.end());
    PRINT_ELEMENTS (coll, "after make_heap():  ");
    // push new element into the heap
    coll.push_back (17);
    push_heap (coll.begin(), coll.end());
    PRINT_ELEMENTS (coll, "after push_heap():  ");
}
on entry:           3 4 5 6 7 5 6 7 8 9 1 2 3 4
after make_heap():  9 8 6 7 7 5 5 3 6 4 1 2 3 4
after push_heap():  17 8 9 7 7 5 6 3 6 4 1 2 3 4 5