function template
<algorithm>

std::sort_heap

default (1)
template <class RandomAccessIterator>  void sort_heap (RandomAccessIterator first, RandomAccessIterator last);
custom (2)
template <class RandomAccessIterator, class Compare>  void sort_heap (RandomAccessIterator first, RandomAccessIterator last,                  Compare comp);
Sort elements of heap
Sorts the elements in the heap range [first,last) into ascending order.

The elements are compared using operator< for the first version, and comp for the second, which shall be the same as used to construct the heap.

The range loses its properties as a heap.

Parameters

first, last
Random-access iterators to the initial and final positions of the heap range to be sorted. The range used is [first,last), which contains all the elements between first and last, including the element pointed by first but not the element pointed by last.
comp
Binary function that accepts two elements in the range as arguments, and returns a value convertible to bool. The value returned indicates whether the element passed as first argument is considered to go before the second in the specific strict weak ordering it defines.
Unless [first,last) is a one-element heap, this argument shall be the same as used to construct the heap.
The function shall not modify any of its arguments.
This can either be a function pointer or a function object.

Return value

none

Example

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// range heap example
#include <iostream>     // std::cout
#include <algorithm>    // std::make_heap, std::pop_heap, std::push_heap, std::sort_heap
#include <vector>       // std::vector

int main () {
  int myints[] = {10,20,30,5,15};
  std::vector<int> v(myints,myints+5);

  std::make_heap (v.begin(),v.end());
  std::cout << "initial max heap   : " << v.front() << '\n';

  std::pop_heap (v.begin(),v.end()); v.pop_back();
  std::cout << "max heap after pop : " << v.front() << '\n';

  v.push_back(99); std::push_heap (v.begin(),v.end());
  std::cout << "max heap after push: " << v.front() << '\n';

  std::sort_heap (v.begin(),v.end());

  std::cout << "final sorted range :";
  for (unsigned i=0; i<v.size(); i++)
    std::cout << ' ' << v[i];

  std::cout << '\n';

  return 0;
}

Output:
initial max heap   : 30
max heap after pop : 20
max heap after push: 99
final sorted range : 5 10 15 20 99


Complexity

Up to linearithmic in the distance between first and last: Performs at most N*log(N) (where N is this distance) comparisons of elements, and up to that many element swaps (or moves).

Data races

The objects in the range [first,last) are modified.

Exceptions

Throws if any of the element comparisons, the element swaps (or moves) or the operations on iterators throws.
Note that invalid arguments cause undefined behavior.

See also