Defined in header <algorithm>  

(1)  
template< class RandomIt > void push_heap( RandomIt first, RandomIt last );  (until C++20)  
template< class RandomIt > constexpr void push_heap( RandomIt first, RandomIt last );  (since C++20)  
(2)  
template< class RandomIt, class Compare > void push_heap( RandomIt first, RandomIt last, Compare comp );  (until C++20)  
template< class RandomIt, class Compare > constexpr void push_heap( RandomIt first, RandomIt last, Compare comp );  (since C++20) 
Inserts the element at the position last  1
into the max heap defined by the range [
first
,
last  1
)
. The first version of the function uses operator<
to compare the elements, the second uses the given comparison function comp
.
first, last    the range of elements defining the heap to modify 
comp    comparison function object (i.e. an object that satisfies the requirements of Compare) which returns true if the first argument is less than the second. The signature of the comparison function should be equivalent to the following:
While the signature does not need to have 
Type requirements  
RandomIt must meet the requirements of LegacyRandomAccessIterator. 

The type of dereferenced RandomIt must meet the requirements of MoveAssignable and MoveConstructible. 
(none).
At most log(N) comparisons where N = std::distance(first, last)
.
A max heap is a range of elements [
f
,
l
)
that has the following properties:
N = l  f
, for all 0 < i < N
, f[(i  1) / 2]
does not compare less than f[i]
. std::push_heap
, in \(\scriptsize \mathcal{O}(\log N)\)𝓞(log N) time. std::pop_heap
, in \(\scriptsize \mathcal{O}(\log N)\)𝓞(log N) time. #include <algorithm> #include <iostream> #include <string_view> #include <vector> void println(std::string_view rem, std::vector<int> const& v) { std::cout << rem; for (int e : v) std::cout << e << ' '; std::cout << '\n'; } int main() { std::vector<int> v {3, 1, 4, 1, 5, 9}; std::make_heap(v.begin(), v.end()); println("after make_heap: ", v); v.push_back(6); println("after push_back: ", v); std::push_heap(v.begin(), v.end()); println("after push_heap: ", v); }
Output:
after make_heap: 9 5 4 1 1 3 after push_back: 9 5 4 1 1 3 6 after push_heap: 9 5 6 1 1 3 4
(C++11)  checks if the given range is a max heap (function template) 
(C++11)  finds the largest subrange that is a max heap (function template) 
creates a max heap out of a range of elements (function template) 

removes the largest element from a max heap (function template) 

turns a max heap into a range of elements sorted in ascending order (function template) 

(C++20)  adds an element to a max heap (niebloid) 
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