Find all the intersecting pairs from a given array

import java.util.*;

// Pair class with two generic types A and B
class Pair<A, B> {
    public A first;
    public B second;

    // Constructor for Pair class
    public Pair(A first, B second)
    {
        this.first = first;
        this.second = second;
    }
}

public class IntervalIntersection {

    // Method to find the intersection of intervals
    public static void
    findIntersection(List<Pair<Integer, Integer> > v, int n)
    {
        // Create two lists, one to hold the interval data
        // and the other to hold the answer
        List<Pair<Integer, Integer> > data
            = new ArrayList<>();
        List<List<Integer> > answer = new ArrayList<>();

        // Loop through each interval
        for (int i = 0; i < n; i++) {
            // Add the start and end of the interval to the
            // data list
            data.add(new Pair<Integer, Integer>(
                v.get(i).first, i));
            data.add(new Pair<Integer, Integer>(
                v.get(i).second, i));
            // Add a new empty list to the answer list for
            // each interval
            answer.add(new ArrayList<>());
        }

        // Sort the data list by the first element of each
        // pair (i.e., the start of each interval)
        Collections.sort(
            data,
            new Comparator<Pair<Integer, Integer> >() {
                public int compare(
                    Pair<Integer, Integer> p1,
                    Pair<Integer, Integer> p2)
                {
                    return p1.first.compareTo(p2.first);
                }
            });

        int curr = 0;
        // Use a TreeSet to keep track of the current
        // intervals The TreeSet is sorted by the second
        // element of each pair (i.e., the index of the
        // interval in the original list)
        Set<Pair<Integer, Integer> > s = new TreeSet<>(
            new Comparator<Pair<Integer, Integer> >() {
                public int compare(
                    Pair<Integer, Integer> p1,
                    Pair<Integer, Integer> p2)
                {
                    if (p1.first.equals(p2.first)) {
                        return p1.second.compareTo(
                            p2.second);
                    }
                    return p1.first.compareTo(p2.first);
                }
            });

        // Loop through each element in the sorted data list
        for (Pair<Integer, Integer> it : data) {
            // If all intervals have been processed, break
            // out of the loop
            if (curr >= n)
                break;
            // If the current interval is in the TreeSet,
            // remove it
            if (s.contains(it))
                s.remove(it);
            else {
                // Otherwise, add the current interval to
                // the TreeSet
                int i = it.second;
                int j = v.get(i).second;
                // Loop through all intervals in the TreeSet
                // that intersect with the current interval
                for (Pair<Integer, Integer> k : s) {
                    if (k.first > j)
                        break;
                    int index = k.second;
                    // Add the intersecting interval to the
                    // answer list for both intervals
                    answer.get(i).add(index);
                    answer.get(index).add(i);
                    curr++;
                    if (curr >= n)
                        break;
                }
                // Add the current interval to the TreeSet
                s.add(new Pair<Integer, Integer>(j, i));
            }
        }
        // Print the result of the intersection
        for (int i = 0; i < n; i++) {
            System.out.print("{" + v.get(i).first + ", "
                             + v.get(i).second + "}"
                             + " is intersecting with: ");
            for (int j = 0; j < answer.get(i).size(); j++)
                System.out.print(
                    "{" + v.get(answer.get(i).get(j)).first
                    + ", "
                    + v.get(answer.get(i).get(j)).second
                    + "}"
                    + " ");
            System.out.println();
        }
    }
    // Driver Code
    public static void main(String[] args)
    {
        int n = 6;
        List<Pair<Integer, Integer> > v = new ArrayList<>();
        v.add(new Pair<Integer, Integer>(9, 12));
        v.add(new Pair<Integer, Integer>(2, 11));
        v.add(new Pair<Integer, Integer>(1, 3));
        v.add(new Pair<Integer, Integer>(6, 10));
        v.add(new Pair<Integer, Integer>(5, 7));
        v.add(new Pair<Integer, Integer>(4, 8));

        findIntersection(v, n);
    }
}