#2433

Find The Original Array of Prefix Xor

medium · verified · 88.3% accepted · 1,508 likes · top 99%

array · bit manipulation

⊣ practice⊣ open on leetcode ↗

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.

Example 1:

Input: pref = [5,2,0,3,1]
Output: [5,7,2,3,2]
Explanation: From the array [5,7,2,3,2] we have the following:
- pref[0] = 5.
- pref[1] = 5 ^ 7 = 2.
- pref[2] = 5 ^ 7 ^ 2 = 0.
- pref[3] = 5 ^ 7 ^ 2 ^ 3 = 3.
- pref[4] = 5 ^ 7 ^ 2 ^ 3 ^ 2 = 1.

Example 2:

Input: pref = [13]
Output: [13]
Explanation: We have pref[0] = arr[0] = 13.

Solution