Difficulty

Hard

Question

Given an integer array nums, and two integers lower and upper, return the number of range sums that lie in [lower, upper] inclusive.

Range sum S(i, j) is defined as the sum of the elements in nums between indices i and j inclusive, where (i ≤ j).

Example 1:

Input: nums = [-2,5,-1], lower = -2, upper = 2
Output: 3
Explanation: The three ranges are : [0,0], [2,2], [0,2] and their respective sums are: -2, -1, 2.

Example 2:

Input: nums = [0], lower = 0, upper = 0
Output: 1

Constraints:

1 <= nums.length <= 10^5
-2^31 <= nums[i] <= 2^31 - 1
-10^5 <= lower <= upper <= 10^5
The answer is guaranteed to fit in a 32-bit integer.

Link

Count of Range Sum

Solution