public static long arrayManipulation(int n, List<List<Integer>> queries) {
        // 1-indexed array
        List<Long> arr = new ArrayList<>() {
            {
                add(Long.MIN_VALUE);
                addAll(Collections.nCopies(n, 0L));
            }
        };
        for (List<Integer> query : queries) {
            Integer a = query.get(0);
            Integer b = query.get(1);
            Integer k = query.get(2);
            arr.set(a, arr.get(a) + k);
            if(b < n) {
                arr.set(b + 1, arr.get(b + 1) - k);
            }
        }
        long answer = 0, sum = 0;
        for(int i = 1; i <= n; i++) {
            sum += arr.get(i);
            answer = Math.max(answer, sum);
        }
        return answer;
    }