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Problems > Sum of Every Range > Editorial

Sum of Every Range — Solution & Editorial

Back to the Problem

Sum-of-ranges = (sum of all subarray maxima) − (sum of all subarray minima); each is a contribution count via monotonic stacks.

Complexity: O(N)

Watch out: The total reaches ~109·N² ≈ 1019 — beyond signed 64-bit; use unsigned/128-bit (Python is safe).