Package g0401_0500.s0454_4sum_ii

Class Solution

  • All Implemented Interfaces:
    
public final class Solution

    454 - 4Sum II.

    Medium

    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:

    • (0, 0, 0, 1) -> nums10 + nums20 + nums30 + nums41 = 1 + (-2) + (-1) + 2 = 0

    • (1, 1, 0, 0) -> nums11 + nums21 + nums30 + nums40 = 2 + (-1) + (-1) + 0 = 0

    Example 2:

    Input: nums1 = 0, nums2 = 0, nums3 = 0, nums4 = 0

    Output: 1

    Constraints:

    • n == nums1.length

    • n == nums2.length

    • n == nums3.length

    • n == nums4.length

    • 1 <= n <= 200

    • <code>-2<sup>28</sup><= nums1i, nums2i, nums3i, nums4i<= 2<sup>28</sup></code>

    • Nested Class Summary

      Nested Classes 
      Modifier and Type Class Description

    • Field Summary

      Fields 
      Modifier and Type Field Description

    • Constructor Summary

      Constructors 
      Constructor Description
      Solution()

    • Enum Constant Summary

      Enum Constants 
      Enum Constant Description

    • Method Summary

      Modifier and Type Method Description
      final Integer fourSumCount(IntArray nums1, IntArray nums2, IntArray nums3, IntArray nums4)

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait