std::push_heap
|   Defined in header  
<algorithm>
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|   template< class RandomIt > 
void push_heap( RandomIt first, RandomIt last );  | 
(1) | |
|   template< class RandomIt, class Compare > 
void push_heap( RandomIt first, RandomIt last,  | 
(2) | |
Inserts the element at the position last-1 into the 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.
Contents | 
[edit] Parameters
| first, last | - | the range of elements defining the heap to modify | |||||||||
| comp | - |   comparison function which returns true if the first argument is less than the second.  The signature of the comparison function should be equivalent to the following: 
 The signature does not need to have const &, but the function must not modify the objects passed to it.  | 
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| Type requirements | |||||||||||
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RandomIt must meet the requirements of RandomAccessIterator.
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 -The type of dereferenced RandomIt must meet the requirements of MoveAssignable and MoveConstructible.
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[edit] Return value
(none)
[edit] Complexity
At most 2×log(N) comparisons where N=std::distance(first, last).
[edit] Notes
A heap is a range of elements [f,l) that has the following properties:
- 
- *f is the largest element in the range
 - a new element can be added using std::push_heap()
 - the first element can be removed using std::pop_heap()
 
 
The actual arrangement of the elements is implementation defined.
[edit] Example
#include <iostream> #include <algorithm> int main() { std::vector<int> v { 3, 1, 4, 1, 5, 9 }; std::make_heap(v.begin(), v.end()); std::cout << "v: "; for (auto i : v) std::cout << i << ' '; std::cout << '\n'; v.push_back(6); std::cout << "before push_heap: "; for (auto i : v) std::cout << i << ' '; std::cout << '\n'; std::push_heap(v.begin(), v.end()); std::cout << "after push_heap: "; for (auto i : v) std::cout << i << ' '; std::cout << '\n'; }
Output:
v: 9 5 4 1 1 3 before push_heap: 9 5 4 1 1 3 6 after push_heap: 9 5 6 1 1 3 4
[edit] See also
|    removes the largest element from a heap   (function template)  | 
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