1720.decode-xored-array
Statement
Metadata
- Link: 解码异或后的数组
- Difficulty: Easy
- Tag:
位运算
数组
未知 整数数组 arr
由 n
个非负整数组成。
经编码后变为长度为 n - 1
的另一个整数数组 encoded
,其中 encoded[i] = arr[i] XOR arr[i + 1]
。例如,arr = [1,0,2,1]
经编码后得到 encoded = [1,2,3]
。
给你编码后的数组 encoded
和原数组 arr
的第一个元素 first
(arr[0]
)。
请解码返回原数组 arr
。可以证明答案存在并且是唯一的。
示例 1:
输入:encoded = [1,2,3], first = 1
输出:[1,0,2,1]
解释:若 arr = [1,0,2,1] ,那么 first = 1 且 encoded = [1 XOR 0, 0 XOR 2, 2 XOR 1] = [1,2,3]
示例 2:
输入:encoded = [6,2,7,3], first = 4
输出:[4,2,0,7,4]
提示:
2 <= n <= 104
encoded.length == n - 1
0 <= encoded[i] <= 105
0 <= first <= 105
Metadata
- Link: Decode XORed Array
- Difficulty: Easy
- Tag:
Bit Manipulation
Array
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
Solution
最后更新: October 11, 2023