#2433 - Find The Original Array of Prefix Xor

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Problem Description

You are given an integer array pref of size n. Find and return the array arr of size n that satisfies:

pref[i] = arr[0] ^ arr[1] ^ ... ^ arr[i].

Note that ^ denotes the bitwise-xor operation.

It can be proven that the answer is unique.

Solution

/**
 * @param {number[]} pref
 * @return {number[]}
 */
var findArray = function(pref) {
  const result = new Array(pref.length);
  result[0] = pref[0];

  for (let i = 1; i < pref.length; i++) {
    result[i] = pref[i] ^ pref[i - 1];
  }

  return result;
};