493. Reverse Pairs

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Given an integer array nums, return the number of reverse pairs in the array. A reverse pair is a pair (i, j) where: - 0 <= i < j < nums.length and - nums[i] > 2 * nums[j]. Example 1: Input: nums = [1,3,2,3,1] Output: 2 Explanation: The reverse pairs are: (1, 4) --> nums[1] = 3, nums[4] = 1, 3 > 2 * 1 (3, 4) --> nums[3] = 3, nums[4] = 1, 3 > 2 * 1 Example 2: Input: nums = [2,4,3,5,1] Outp

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solution.cppC++17

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