priority-queue-stl.cpp

    /*

     * C++ Program to Implement Priority_queue in Stl

     */

    #include <iostream>

    #include <queue>

    #include <string>

    #include <cstdlib>

    using namespace std;

    int main()

    {

        priority_queue<int> pq;

        int choice, item;

        while (1)

        {

            cout<<"\n---------------------"<<endl;

            cout<<"Priority Queue Implementation in Stl"<<endl;

            cout<<"\n---------------------"<<endl;

            cout<<"1.Insert Element into the Priority Queue"<<endl;

            cout<<"2.Delete Element from the Priority Queue"<<endl;

    	cout<<"3.Size of the Priority Queue"<<endl;

            cout<<"4.Top Element of the Priority Queue"<<endl;

            cout<<"5.Exit"<<endl;

            cout<<"Enter your Choice: ";

            cin>>choice;

            switch(choice)

            {

            case 1:

                cout<<"Enter value to be inserted: ";

                cin>>item;

                pq.push(item);

                break;

            case 2:

                item = pq.top();

                if (!pq.empty())

                {

                    pq.pop();

                    cout<<"Element "<<item<<" Deleted"<<endl;

                }

                else

                {

                    cout<<"Priority Queue is Empty"<<endl;

                }

                break;

            case 3:

                cout<<"Size of the Queue: ";

    	    cout<<pq.size()<<endl;

                break;

            case 4:

                cout<<"Top Element of the Queue: ";

                cout<<pq.top()<<endl;

                break;

            case 5:

                exit(1);

    	    break;

            default:

                cout<<"Wrong Choice"<<endl;

            }

        }

        return 0;

    }