Package g1401_1500.s1442_count_triplets_that_can_form_two_arrays_of_equal_xor

Class Solution

  • public class Solution
extends Object
    1442 - Count Triplets That Can Form Two Arrays of Equal XOR.

    Medium

    Given an array of integers arr.

    We want to select three indices i, j and k where (0 <= i < j <= k < arr.length).

    Let’s define a and b as follows:

    • a = arr[i] ^ arr[i + 1] ^ ... ^ arr[j - 1]
    • b = arr[j] ^ arr[j + 1] ^ ... ^ arr[k]

    Note that ^ denotes the bitwise-xor operation.

    Return the number of triplets (i, j and k) Where a == b.

    Example 1:

    Input: arr = [2,3,1,6,7]

    Output: 4

    Explanation: The triplets are (0,1,2), (0,2,2), (2,3,4) and (2,4,4)

    Example 2:

    Input: arr = [1,1,1,1,1]

    Output: 10

    Constraints:

    • 1 <= arr.length <= 300
    • 1 <= arr[i] <= 108

    • Constructor Detail

      • Solution

        public Solution()

    • Method Detail

      • countTriplets

        public int countTriplets​(int[] arr)