The problem is to create a third list, nums3, by taking the XOR of one number from nums1 with one number from nums2.The naive approach calculates the XOR for every pair of numbers from nums1 and nums2, which is computationally expensive for large inputs.The optimized solution improves efficiency by taking advantage of the mathematical properties of XOR and avoids explicitly iterating over all pairs.The approach has a time complexity of O(n+m), where n and m are the lengths of nums1 and nums2, respectively.