Longest Window Whose Largest Pair Difference Meets a Limit

### Problem Return the length of the longest nonempty contiguous subarray of nums in which every pair of values differs in absolute value by at most limit. Compare every pair, not only neighbors. ```cpp class Solution { public: int longestSubarray(vector<int>& nums, int limit); }; ``` ### Examples **Example 1:** ```text Input: nums = [1,3,2,6], limit = 2 Output: 3 Explanation: The window[1,3,2] has maximum3 minus minimum1 equal to2. The whole array fails. ``` **Example 2:** ```text Input: nums = [5,5,6,6,6], limit = 0 Output: 3 Explanation: Only equal-valued runs qualify; the last three6s are longest. ``` ### Constraints - nums has length 1 to 100000. - `1 <= nums[i] <= 1000000000`. - `0 <= limit <= 1000000000`. ### Contract considerations A singleton is always valid under the nonnegative limit. ```hint Read the boundary condition Every pair in the chosen subarray must meet the limit. Check a zero limit, repeated values, and singleton subarrays. ``` ### Boundary reminders A singleton is always valid under the nonnegative limit.