2302. Count Subarrays With Score Less Than K 
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Problem
The score of an array is defined as the product of its sum and its length.
- For example, the score of
[1, 2, 3, 4, 5]is(1 + 2 + 3 + 4 + 5) * 5 = 75.
Given a positive integer array nums and an integer k, return the number of non-empty subarrays of nums whose score is strictly less than k.
A subarray is a contiguous sequence of elements within an array.
Example 1:
Input: nums = [2,1,4,3,5], k = 10 Output: 6 Explanation: The 6 subarrays having scores less than 10 are: - [2] with score 2 * 1 = 2. - [1] with score 1 * 1 = 1. - [4] with score 4 * 1 = 4. - [3] with score 3 * 1 = 3. - [5] with score 5 * 1 = 5. - [2,1] with score (2 + 1) * 2 = 6. Note that subarrays such as [1,4] and [4,3,5] are not considered because their scores are 10 and 36 respectively, while we need scores strictly less than 10.
Example 2:
Input: nums = [1,1,1], k = 5 Output: 5 Explanation: Every subarray except [1,1,1] has a score less than 5. [1,1,1] has a score (1 + 1 + 1) * 3 = 9, which is greater than 5. Thus, there are 5 subarrays having scores less than 5.
Constraints:
1 <= nums.length <= 1051 <= nums[i] <= 1051 <= k <= 1015