Count the index triples (i, j, k) satisfying 0 <= i < j <= k < arr.length for which the XOR of arr[i] through arr[j - 1] equals the XOR of arr[j] through arr[k]. Both ranges are nonempty. Return the number of such triples.
Example 1:
Input: arr = [4,4]
Output: 1Explanation: The only eligible triple is (0, 1, 1). Its two ranges are [4] and [4], which have equal XOR.
Example 2:
Input: arr = [1,2,4]
Output: 0Explanation: The eligible pairs of adjacent nonempty ranges have XORs (1,2), (1,6), (3,4), or (2,4). None are equal.
Example 3:
Input: arr = [3,3,3]
Output: 2Explanation: The triples (0, 1, 1) and (1, 2, 2) each compare two single entries equal to 3. The other eligible triples do not have equal XOR.
Constraints:
1 <= arr.length <= 3001 <= arr[i] <= 100000000