1442. Count Triplets That Can Form Two Arrays of Equal XOR

https://leetcode.com/problems/count-triplets-that-can-form-two-arrays-of-equal-xor

Description

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

Example 3:

**Input:** arr = [2,3]

**Output:** 0

Example 4:

**Input:** arr = [1,3,5,7,9]

**Output:** 3

Example 5:

**Input:** arr = [7,11,12,9,5,2,7,17,22]

**Output:** 8

Constraints:

• 1 <= arr.length <= 300

• 1 <= arr[i] <= 10^8

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