public static long arrayManipulation(int n, List<List<Integer>> queries) {
        Map<Integer, Long> sum = new TreeMap<>(); // order by key
        for (List<Integer> list : queries) {
            int a = list.get(0);
            int b = list.get(1);
            long k = list.get(2);
            sum.put(a, sum.getOrDefault(a, 0L) + k);
            sum.put(b + 1, sum.getOrDefault(b + 1, 0L) - k);
        }

        long max = 0L;
        long current = 0L;
        for (long value : sum.values()) {
            current += value;
            max = Math.max(max, current);
        }
        return max;

    }