Import all necessary libraries: #include <bits/stdc++.h>

STL(standard template library) components:

stack:

LIFO(Last in first out) (pancake).

The functions associated with stack are:

Function Name	Description	Time Complexity
`empty()`	Returns whether the stack is empty	O(1)
`size()`	Returns the size of the stack.	O(1)
`top()`	Returns a reference to the topmost element of the stack	O(1)
`push(g)`	Adds the element ‘g’ at the top of the stack	O(1)
`pop()`	Deletes the most recent entered element of the stack	O(1)

swap(): This function is used to swap the contents of one stack with another stack of the same type, but the size may vary. Syntax :

stackname1.swap(stackname2)

Time Complexity : O(1)

queue:

FIFO (first in, first out).

Function Name	Description	Time Complexity
`queue::empty()`	Returns whether the queue is empty. It returns true if the queue is empty otherwise returns false.	O(1)
`queue::size()`	Returns the size of the queue.	O(1)
`queue::swap()`	Exchange the contents of two queues but the queues must be of the same data type, although sizes may differ.	O(1)
`queue::emplace()`	Insert a new element into the queue container, and the new element is added to the end of the queue.	O(1)
`queue::front()`	Returns a reference to the first element of the queue.	O(1)
`queue::back()`	Returns a reference to the last element of the queue.	O(1)
`queue::push(g)`	Adds the element ‘g’ at the end of the queue.	O(1)
`queue::pop()`	Deletes the first element of the queue.	O(1)

Heap (priority queue):

make_heap(): This is used to convert a container of values, such as vectors, into heaps (max heap unless we provide a comparator function to turn it into a min-heap).

front() returns the maximum element of the heap.

vector<int> v;
make_heap(v.begin(), v.end());
cout<<v.front()<<endl;

to create min heap with make_heap()

struct greaters{
	bool operator()(const long& a,const long& b) const{
	    return a>b;
	}
};

make_heap(v.begin(),v.end(), greaters());