FUNCTORS AND PRIORITY QUEUE IN STL IN CPP

#include<bits/stdc++.h>
using namespace std;

class car
{
public:
    int x;
    int y;
    int id;

    car(int id,int x,int y)
    {
        this->id=id;
        this->x=x;
        this->y=y;
    }

    int distance()
    {
        return x*x+y*y;
    }

    void print()
    {
        cout<<"ID "<<id;
        cout<<"LOCATION :"<<x<<" , "<<y<<endl;
    }

};

// functors - Functional Objects

class carcompare{

public:
    // Method to overload() operator

    bool operator()(car a, car b)
    {
        return a.distance() > b.distance();
    }




};










int main()
{
   //priority_queue<int,vector<int>,greater<int> >pq;
   priority_queue<car,vector<car>,carcompare>pq;

   int x[10]={5,6,17,18,9,11,0,3};
   int y[10]={1,-2,8,9,10,91,1,2};

   //Insert these 8 cars in the priority queue.
   for(int i=0;i<8;i++)
   {
       car c(i,x[i],y[i]);
       pq.push(c);
   }

   // Heap-max!!

   int poppings=1;

   while(!pq.empty() && poppings<=3)
   {
       car p=pq.top();
       p.print();
       pq.pop();
       poppings++;

   }


}