Given an integer array arr, remove a subarray (can be empty) from arr such that the remaining elements in arr are non-decreasing. A subarray is a contiguous subsequence of the array. Return the length of the shortest subarray to remove. Example 1: Input: arr = [1,2,3,10,4,2,3,5] Output: 3 Explanation: The shortest subarray we can remove is [10,4,2] of length 3. The remaining elements after that will be [1,2,3,3,5] which are sorted. Another correct solution is to remove the subarray [3,10,4]. Example 2: Input: arr = [5,4,3,2,1] Output: 4 Explanation: Since the array is strictly decreasing, we can only keep a single element. Therefore we need to remove a subarray of length 4, either [5,4,3,2] or [4,3,2,1]. Example 3: Input: arr = [1,2,3] Output: 0 Explanation: The array is already non-decreasing. We do not need to remove any elements. Example 4: Input: arr = [1] Output: 0 Constraints: 1 <= arr.length <= 10^5 0 <= arr[i] <= 10^9