We have an array of integers, `nums`, and an array of `requests` where `requests[i] = [starti, endi]`. The `ith` request asks for the sum of `nums[starti] + nums[starti + 1] + ... + nums[endi - 1] + nums[endi]`. Both `starti` and `endi` are 0-indexed.

Return the maximum total sum of all requests among all permutations of `nums`.

Since the answer may be too large, return it modulo `109 + 7`.

Example 1:

    Input: nums = [1,2,3,4,5], requests = [[1,3],[0,1]]
    Output: 19
    Explanation: One permutation of nums is [2,1,3,4,5] with the following result:
    requests[0] -> nums[1] + nums[2] + nums[3] = 1 + 3 + 4 = 8
    requests[1] -> nums[0] + nums[1] = 2 + 1 = 3
    Total sum: 8 + 3 = 11.
    A permutation with a higher total sum is [3,5,4,2,1] with the following result:
    requests[0] -> nums[1] + nums[2] + nums[3] = 5 + 4 + 2 = 11
    requests[1] -> nums[0] + nums[1] = 3 + 5  = 8
    Total sum: 11 + 8 = 19, which is the best that you can do.

Example 2:

    Input: nums = [1,2,3,4,5,6], requests = [[0,1]]
    Output: 11
    Explanation: A permutation with the max total sum is [6,5,4,3,2,1] with request sums [11].

Example 3:

    Input: nums = [1,2,3,4,5,10], requests = [[0,2],[1,3],[1,1]]
    Output: 47
    Explanation: A permutation with the max total sum is [4,10,5,3,2,1] with request sums [19,18,10].

Constraints:

- `n == nums.length`
- `1 <= n <= 105`
- `0 <= nums[i] <= 105`
- `1 <= requests.length <= 105`
- `requests[i].length == 2`
- `0 <= starti <= endi < n`