public static long arrayManipulation(int n, List> queries) { long[] arr = new long[n]; long sum = 0; long max = 0;

    for(int i=0; i < queries.Count; i++)
    {
        int a = queries[i][0] - 1;
        int b = queries[i][1] - 1;
        int k = queries[i][2];

        for(int col=a;col<=b;col++)
        {
            arr[col] += k;
            max = Math.Max(max,arr[col]);
        }
    }

    return max;
}