An integer array “original” is transformed into a doubled array “changed” by appending twice the value of every element in “original”, and then randomly shuffling the resulting array.Given an array “changed”, return “original” if “changed” is a doubled array. If “changed” is not a doubled array, return an empty array. The elements in “original” may…

Given an array nums with n integers, your task is to check if it could become non-decreasing by modifying at most one element.We define an array as non-decreasing if nums[i] <= nums[i+1] holds for every i (0-based) such that 0 <= i <= n-2. English Summary (Approach)Single pass. Count violations where nums[i] > nums[i+1]. If…