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

Understand how to count triplets (i, j, k) in an array such that the XOR of two defined subarrays are equal. Explore the application of bitwise XOR operations with prefix XOR optimizations and hash maps to achieve an efficient solution reducing time complexity from O(n^3) to O(n). This lesson helps you apply bitwise manipulation techniques to solve complex coding interview problems efficiently.

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 ...