454. 4Sum II

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Given four integer arrays nums1, nums2, nums3, and nums4 all of length n, return the number of tuples (i, j, k, l) such that: - 0 <= i, j, k, l < n - nums1[i] + nums2[j] + nums3[k] + nums4[l] == 0 Example 1: Input: nums1 = [1,2], nums2 = [-2,-1], nums3 = [-1,2], nums4 = [0,2] Output: 2 Explanation: The two tuples are: 1. (0, 0, 0, 1) -> nums1[0] + nums2[0] + nums3[0] + nums4[1] = 1 + (-2) +

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solution.cppC++17

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