mirror of
https://github.com/halfrost/LeetCode-Go.git
synced 2025-07-05 08:27:30 +08:00
72 lines
2.8 KiB
Markdown
Executable File
72 lines
2.8 KiB
Markdown
Executable File
# [393. UTF-8 Validation](https://leetcode.com/problems/utf-8-validation/)
|
||
|
||
|
||
|
||
## 题目
|
||
|
||
A character in UTF8 can be from **1 to 4 bytes** long, subjected to the following rules:
|
||
|
||
1. For 1-byte character, the first bit is a 0, followed by its unicode code.
|
||
2. For n-bytes character, the first n-bits are all one's, the n+1 bit is 0, followed by n-1 bytes with most significant 2 bits being 10.
|
||
|
||
This is how the UTF-8 encoding would work:
|
||
|
||
Char. number range | UTF-8 octet sequence
|
||
(hexadecimal) | (binary)
|
||
--------------------+---------------------------------------------
|
||
0000 0000-0000 007F | 0xxxxxxx
|
||
0000 0080-0000 07FF | 110xxxxx 10xxxxxx
|
||
0000 0800-0000 FFFF | 1110xxxx 10xxxxxx 10xxxxxx
|
||
0001 0000-0010 FFFF | 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
|
||
|
||
Given an array of integers representing the data, return whether it is a valid utf-8 encoding.
|
||
|
||
**Note:**The input is an array of integers. Only the **least significant 8 bits** of each integer is used to store the data. This means each integer represents only 1 byte of data.
|
||
|
||
**Example 1:**
|
||
|
||
data = [197, 130, 1], which represents the octet sequence: 11000101 10000010 00000001.
|
||
|
||
Return true.
|
||
It is a valid utf-8 encoding for a 2-bytes character followed by a 1-byte character.
|
||
|
||
**Example 2:**
|
||
|
||
data = [235, 140, 4], which represented the octet sequence: 11101011 10001100 00000100.
|
||
|
||
Return false.
|
||
The first 3 bits are all one's and the 4th bit is 0 means it is a 3-bytes character.
|
||
The next byte is a continuation byte which starts with 10 and that's correct.
|
||
But the second continuation byte does not start with 10, so it is invalid.
|
||
|
||
## 题目大意
|
||
|
||
UTF-8 中的一个字符可能的长度为 1 到 4 字节，遵循以下的规则：
|
||
|
||
对于 1 字节的字符，字节的第一位设为 0，后面 7 位为这个符号的 unicode 码。
|
||
对于 n 字节的字符 (n > 1)，第一个字节的前 n 位都设为 1，第 n+1 位设为 0，后面字节的前两位一律设为 10。剩下的没有提及的二进制位，全部为这个符号的 unicode 码。
|
||
这是 UTF-8 编码的工作方式：
|
||
|
||
```c
|
||
Char. number range | UTF-8 octet sequence
|
||
(hexadecimal) | (binary)
|
||
--------------------+---------------------------------------------
|
||
0000 0000-0000 007F | 0xxxxxxx
|
||
0000 0080-0000 07FF | 110xxxxx 10xxxxxx
|
||
0000 0800-0000 FFFF | 1110xxxx 10xxxxxx 10xxxxxx
|
||
0001 0000-0010 FFFF | 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
|
||
|
||
```
|
||
|
||
给定一个表示数据的整数数组，返回它是否为有效的 utf-8 编码。
|
||
|
||
注意:
|
||
|
||
输入是整数数组。只有每个整数的最低 8 个有效位用来存储数据。这意味着每个整数只表示 1 字节的数据。
|
||
|
||
|
||
## 解题思路
|
||
|
||
- 这一题看似很复杂，其实严格按照 UTF8 定义来模拟就可以了。
|
||
|