Count the Number of Incremovable Subarrays II
You are given a 0-indexed array of positive integers nums.
A subarray of nums is called incremovable if nums becomes strictly increasing after removing the subarray. For example, the subarray [3, 4] is an incremovable subarray of [5, 3, 4, 6, 7] because removing this subarray changes the array [5, 3, 4, 6, 7] to [5, 6, 7], which is strictly increasing.
Return the total number of incremovable subarrays of nums.
Note that an empty array is considered strictly increasing.
A subarray is a contiguous non-empty sequence of elements within an array.
Example 1
Input
nums = [1,2,3,4]Output
10The 10 incremovable subarrays are [1], [2], [3], [4], [1,2], [2,3], [3,4], [1,2,3], [2,3,4], and [1,2,3,4], because removing any one of them makes nums strictly increasing.
Example 2
Input
nums = [6,5,7,8]Output
7The 7 incremovable subarrays are [5], [6], [5,7], [6,5], [5,7,8], [6,5,7], and [6,5,7,8], and there are only 7 such subarrays.
Constraints
- 1 <= nums.length <= 10^5
- 1 <= nums[i] <= 10^9
Asked at 3 companies
Practice questions like this out loud in a mock coding interview with a live AI interviewer. First one free.