There is a hidden integer array arr that consists of n non-negative integers.
It was encoded into another integer array encoded of length n - 1, such that encoded[i] = arr[i] XOR arr[i + 1]. For example, if arr = [1,0,2,1], then encoded = [1,2,3].
You are given the encoded array. You are also given an integer first, that is the first element of arr, i.e. arr[0].
Return the original array arr. It can be proved that the answer exists and is unique.
Example 1:
Input: encoded = [1,2,3], first = 1 Output: [1,0,2,1] Explanation: If arr = [1,0,2,1], then first = 1 and encoded = [1 XOR 0, 0 XOR 2, 2 XOR 1] = [1,2,3] Example 2:
Input: encoded = [6,2,7,3], first = 4 Output: [4,2,0,7,4]
Constraints:
2 <= n <= 104 encoded.length == n - 1 0 <= encoded[i] <= 105 0 <= first <= 105
public class Solution {
public int[] Decode(int[] encoded, int first) {
var arr = new int[encoded.Length+1];
arr[0]=first;
for(int i=1;i<encoded.Length+1;i++){
arr[i]=arr[i-1] ^ encoded[i-1];
}
return arr;
}
}Time Complexity: O(n)
Space Complexity: O(n)
