Shortest Combined Length of Two Disjoint Target-Sum Windows

### Problem Find two nonempty,non-overlapping contiguous subarrays of arr, each summing to target. Return the smallest sum of their lengths,or -1 when no such pair exists. Return the length value rather than the windows themselves. ```cpp class Solution { public: int minSumOfLengths(vector<int>& arr, int target); }; ``` ### Examples **Example 1:** ```text Input: arr = [1,2,1,2], target = 3 Output: 4 Explanation: The first two and last two entries form disjoint target-sum windows. Every target-sum window needs at least two entries. ``` **Example 2:** ```text Input: arr = [1,1,1], target = 2 Output: -1 Explanation: The two length2 target-sum windows overlap,so they cannot form a valid pair. ``` ### Constraints - arr has length 1 to 100000. - `1 <= arr[i] <= 1000`. - `1 <= target <= 100000000`. ### Contract considerations The phrase multiple answers refers to window choices; the returned minimum integer is deterministic. ```hint Read the boundary condition Both target-sum subarrays must be nonempty and disjoint. Minimize their combined length and account for a missing feasible pair. ``` ### Boundary reminders The phrase multiple answers refers to window choices; the returned minimum integer is deterministic.