make_heap: rearrange elements in a range such that they form a heap

make_heap(begin,end, comparator)

comparator is a boolean function optional

pop_heap

push_heap

if v is a vector then

```
std::make_heap (v.begin(),v.end());
```

v.front() will give you maximum [default is maxheap without comparator]

You can pass the comparator function to each operation to maintain the heap property.

get the element by v.front()

Now pop the element using

`pop_heap (v.begin(),v.end()); // can also pass comparator here `

Pop element from heap and rearranges the elements in the heap range

`[first,last)`

in such a way that the part considered a heap is shortened by one: The element with the highest value is moved to `(last-1)`

.
While the element with the highest value is moved from

`first`to`(last-1)`

(which now is out of the heap), the other elements are reorganized in such a way that the range `[first,last-1)`

preserves the properties of a heap.Now to actually remove the element from the vector you can use:

`v.pop_back();`

So a range can be organized into a heap by calling make_heap. After that, its heap properties are preserved if elements are added and removed from it using push_heap and pop_heap, respectively.

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

push_heap (v.begin(),v.end());

Given a heap in the range `[first,last-1)`

, this function extends the range considered a heap to `[first,last)`

by placing the value in `(last-1)`

into its corresponding location within it.

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

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