Minimise Expenses - JAVA

package com.company;
import kotlin.Pair;

import java.util.*;


public class Problem {

    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int[][] expenses = new int[n][2];

        for(int i=0; i < n; i++){
            expenses[i][0] = sc.nextInt();
            expenses[i][1] = sc.nextInt();
        }
        int result = minimiseExpenses(expenses, n);
        System.out.println(result);
    }


    public static int minimiseExpenses(int[][] expenses, int n) {
        ArrayList<Pair<Integer, Integer>> list = new ArrayList<>();

        for(int i=0; i < n; i++){
            list.add(i, new Pair<>(expenses[i][0] - expenses[i][1], i));
        }

        Collections.sort(list, new Comparator<Pair<Integer, Integer>>() {
            @Override
            public int compare(Pair<Integer, Integer> o1, Pair<Integer, Integer> o2) {
                return o1.getFirst() - o2.getFirst();
            }
        });

        int totalExpense = 0;
        for(int i=0; i < n/2; i++)
            totalExpense += expenses[list.get(i).getSecond()][0];

        for(int i=n/2; i < n; i++)
            totalExpense += expenses[list.get(i).getSecond()][1];


        return totalExpense;

    }
}