Measure the Smallest Segment that Needs Sorting

### Problem Return the minimum length of one contiguous segment whose nondecreasing sort would make all of nums nondecreasing. Return zero when nums is already sorted. ```cpp class Solution { public: int findUnsortedSubarray(vector<int>& nums); }; ``` ### Examples **Example 1:** ```text nums = [1,5,3,4,6] Output: 3 Explanation: Sorting [5,3,4] fixes the whole array. ``` **Example 2:** ```text nums = [2,2,2] Output: 0 Explanation: Equality is allowed in sorted order. ``` ### Constraints - Input length: 1..10000. Every number lies in -100000..100000. ### Clarifying Questions Find inversion boundaries that account for distant values and recognize an already-sorted array. ```hint Read the boundary condition Which values are smaller than something already seen from the left? ``` ### Contract considerations Find inversion boundaries that account for distant values and recognize an already-sorted array. ### Optional follow-up Can you solve the problem in O(n) time?