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All topics›JavaScript›Arrays & strings

Range Sum Query — Immutable

intermediatelayer B2 · Arrays & strings5 tests

Build a class NumArray that answers repeated range-sum queries over a fixed array.

  • new NumArray(nums) — the constructor may do O(n) work
  • sumRange(i, j) — returns the sum of nums[i] through nums[j] inclusive, and must run in O(1)
  • The array never changes after construction, so all the work belongs in the constructor
  • sumRange(i, i) returns a single element

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