adventofcode Day 1 Part 2

import java.util.ArrayList;
import java.util.Scanner;

public class AoC2 {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        ArrayList<Integer> list = new ArrayList<>();
        ArrayList<Integer> sums = new ArrayList<>();

        while (true) {
            int input = Integer.valueOf(scanner.nextLine());
            if (input == -1) {
                break;
            }
            list.add(input);
        }

        for (int i = 0; i <= list.size() - 3; i++) {
                int sum = list.get(i) + list.get(i + 1) + list.get(i + 2);
                sums.add(sum);
        }

        int increased = 0;
        for (int z = 1; z < sums.size(); z++) {
            if (sums.get(z) > sums.get(z - 1)) {
                increased++;
            }
        }
        System.out.println(increased);

    }

}