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Solution: Count Triplets That Can Form Two Arrays of Equal XOR

Explore how to find triplets of indices in an array where the XOR of two subarrays are equal. Understand the prefix XOR technique and hash maps to optimize from O(n^3) to O(n) time, enabling efficient bitwise manipulation for coding interview problems.

Statement

Given an array of integers, arr, we need to find three indices, i, j, and k, such that 00\leq i << j \leq k << arr.length.

We define two values, a and b, as follows:

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

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

Note: ^ denotes the bitwise XOR operation.

Return the count of triplets (i, j, k) for which a is equal to b.

Constraints:

  • 11 \leq arr.length 300\leq 300

  • 11 \leq ...