C++ program to implement Priority Queue using Template

/* C++ program Priority Queue using Template */

#include<iostream>
#include<stdlib.h>
using namespace std;

template <class T>
class PQ
{
    struct node
    {
        T data;
        int priority;
        struct node *link;
    }*head;
    
    public: void insert(T,int);
            void delet();
            void display();
};

template <class T>
void PQ<T> :: insert(T item,int prio)
{
    struct node *p,*temp;
    temp=new node;
    temp->data=item;
    temp->priority=prio;
    if(head==NULL || prio<head->priority)
    {
        temp->link=head;
        head=temp;
    }
    else
    {
        p=head;
        while(p->link!=NULL && p->link->priority<=prio)
            p=p->link;
        temp->link=p->link;
        p->link=temp;
    }
}

template <class T>
void PQ<T> :: delet()
{
    if(head==NULL)
        cout<<"Queue underflow";
    else
    {
        struct node *temp;
        cout<<"\nDeleted item is "<<head->data;
        temp=head;
        head=head->link;
        free(temp);
    }
}

template <class T>
void PQ<T> :: display()
{
    if(head==NULL)
        cout<<"Queue underflow";
    else
    {
        cout<<"\nPriority Queue is\n";
        struct node *temp;       
        for(temp=head;temp!=NULL;temp=temp->link)
            cout<<"\t"<<temp->data;
    }
}

int main()
{
    PQ <int>p;
    while(1)
    {
        cout<<"\n1.Insert\n2.Delete\n3.Display\n4.Exit";
        cout<<"\nEnter choice: ";
        int ch;
        cin>>ch;
        switch(ch)
        {
            case 1: int item,prio;
                    cout<<"\nEnter data to insert: ";
                    cin>>item;
                    cout<<"\nEnter Priority of "<<item<<": ";
                    cin>>prio;
                    p.insert(item,prio);
                    break;
            case 2: p.delet();
                    break;
            case 3: p.display();
                    break;   
            case 4: exit(0);
            default: cout<<"\n wrong choice given...."; 
        }   
    }
    return(0);
}

Output