Maximize the Total of Two Disjoint Fixed-Length Segments

### Problem Choose two non-overlapping contiguous subarrays of `nums`, one of length firstLen and the other of length secondLen. Either length may occur first in the array. Return their maximum combined sum. The segments may be adjacent or separated. ```cpp class Solution { public: int maxSumTwoNoOverlap(vector<int>& nums, int firstLen, int secondLen); }; ``` ### Examples **Example 1:** ```text Input: nums = [5,1,4,2,6], firstLen = 1, secondLen = 2 Output: 13 Explanation: Use singleton[5] and the final pair[2,6], totaling13. The possible pair sums are6,5,6,and8; their best disjoint singletons give totals12,11,12,and13. ``` **Example 2:** ```text Input: nums = [1,2,3,4], firstLen = 2, secondLen = 2 Output: 10 Explanation: Both required segments together use the full array, so[1,2] and[3,4] attain10. ``` ### Constraints - `1 <= firstLen,secondLen <= 1000`. - `2 <= firstLen+secondLen <= 1000`. - `firstLen+secondLen <= nums.length <= 1000`. - `0 <= nums[i] <= 1000`. ### Contract considerations The answer is a sum, not the selected indices or an arbitrary placement. ```hint Read the boundary condition For each right window, cache the best eligible left window rather than testing every pair. ``` ### Boundary reminders The answer is a sum, not the selected indices or an arbitrary placement.