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Prefix Sum for Range/Subarray
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Prefix Sum for Range/Subarray

EasyPython

Problem

Supermicro monitoring software stores integer telemetry readings in chronological order. Given the readings and many inclusive range queries, return the sum of each requested range efficiently.

Build a prefix-sum array so that each query can be answered without scanning every element in its range.

Formal Specification

Implement range_sum_queries(nums, queries).

  • nums is a list of integers, where nums[i] is the reading at index i.
  • queries is a list of two-element lists [left, right] with inclusive, zero-based bounds.
  • Return a list of integers where the result at position k is the sum of nums[left:right + 1] for queries[k].
  • The input array is not modified.

Constraints

  • 1 <= nums.length <= 100,000
  • 1 <= queries.length <= 100,000
  • -10^9 <= nums[i] <= 10^9
  • 0 <= left <= right < nums.length
  • Each query uses inclusive, zero-based indices

Function Signature

def range_sum_queries(nums, queries):
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