Double ended priority queue in C++ Program

In this tutorial, we are going to create a double-ended priority queue using the set in c++.

Let's see the steps to create a double-ended queue.

• Create a struct with a name as you wish.

• Create a variable for the queue using the set.

• size method that returns the size of the queue.

• is_empty method that returns whether the queue is empty or not.

• insert method to insert a new element into the queue.

• get_start method that returns an element from the left side of the queue.

• get_end method that returns the element from the right side of the queue.

• delete_start method that deletes the first element from the left side.

• delete_end method deletes the first element from the right side.

Example

Let's see the code.

 Live Demo

#include <bits/stdc++.h> using namespace std; struct doubleEndedQueue {    set<int> s;    int size() {       return s.size();    }    string is_empty() {       return s.size() == 0 ? "True" : "False";    }    void insert(int x) {       s.insert(x);    }    int get_start() {       return *(s.begin());    }    int get_end() {       return *(s.rbegin());    }    void delete_start() {       if (s.size() == 0) {          return;       }         s.erase(s.begin());    }    void delete_end() {       if (s.size() == 0) {          return;       }       auto end = s.end();       end--;       s.erase(end);    } }; int main() {    doubleEndedQueue d;    cout << "is empty: " << d.is_empty() << endl;    d.insert(1);    d.insert(2);    d.insert(3);    d.insert(4);    d.insert(5);    cout << "is empty: " << d.is_empty() << endl;    cout << "end: " << d.get_end() << endl;    d.delete_end();    cout << "end: " << d.get_end() << endl;    cout << "start: " << d.get_start() << endl;    d.delete_start();    cout << "start: " << d.get_start() << endl;    return 0; }

Output

If you run the above code, then you will get the following result.

is empty: True is empty: False end: 5 end: 4 start: 1 start: 2

Conclusion

If you have any queries in the tutorial, mention them in the comment section.