{ "data": { "question": { "questionId": "393", "questionFrontendId": "393", "categoryTitle": "Algorithms", "boundTopicId": 1862, "title": "UTF-8 Validation", "titleSlug": "utf-8-validation", "content": "

Given an integer array data representing the data, return whether it is a valid UTF-8 encoding (i.e. it translates to a sequence of valid UTF-8 encoded characters).

\n\n

A character in UTF8 can be from 1 to 4 bytes long, subjected to the following rules:

\n\n
    \n\t
  1. For a 1-byte character, the first bit is a 0, followed by its Unicode code.
    2. \n\t
  2. For an n-bytes character, the first n bits are all one's, the n + 1 bit is 0, followed by n - 1 bytes with the most significant 2 bits being 10.
    3. \n
\n\n

This is how the UTF-8 encoding would work:

\n\n
\n     Number of Bytes   |        UTF-8 Octet Sequence\n                       |              (binary)\n   --------------------+-----------------------------------------\n            1          |   0xxxxxxx\n            2          |   110xxxxx 10xxxxxx\n            3          |   1110xxxx 10xxxxxx 10xxxxxx\n            4          |   11110xxx 10xxxxxx 10xxxxxx 10xxxxxx\n
\n\n

x denotes a bit in the binary form of a byte that may be either 0 or 1.

\n\n

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.

\n\n

 

\n

Example 1:

\n\n
\nInput: data = [197,130,1]\nOutput: true\nExplanation: data represents the octet sequence: 11000101 10000010 00000001.\nIt is a valid utf-8 encoding for a 2-bytes character followed by a 1-byte character.\n
\n\n

Example 2:

\n\n
\nInput: data = [235,140,4]\nOutput: false\nExplanation: data represented the octet sequence: 11101011 10001100 00000100.\nThe first 3 bits are all one's and the 4th bit is 0 means it is a 3-bytes character.\nThe next byte is a continuation byte which starts with 10 and that's correct.\nBut the second continuation byte does not start with 10, so it is invalid.\n
\n\n

 

\n

Constraints:

\n\n\n", "translatedTitle": "UTF-8 编码验证", "translatedContent": "

给定一个表示数据的整数数组 data ，返回它是否为有效的 UTF-8 编码。

\n\n

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：

\n\n
    \n\t
  1. 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。
    2. \n\t
  2. 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。
    3. \n
\n\n

这是 UTF-8 编码的工作方式：

\n\n
\n      Number of Bytes  |        UTF-8 octet sequence\n                       |              (binary)\n   --------------------+---------------------------------------------\n            1          | 0xxxxxxx\n            2          | 110xxxxx 10xxxxxx\n            3          | 1110xxxx 10xxxxxx 10xxxxxx\n            4          | 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx\n
\n\n

x 表示二进制形式的一位，可以是 0 或 1。

\n\n

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。

\n\n

 

\n\n

示例 1：

\n\n
\n输入：data = [197,130,1]\n输出：true\n解释：数据表示字节序列:11000101 10000010 00000001。\n这是有效的 utf-8 编码，为一个 2 字节字符，跟着一个 1 字节字符。\n
\n\n

示例 2：

\n\n
\n输入：data = [235,140,4]\n输出：false\n解释：数据表示 8 位的序列: 11101011 10001100 00000100.\n前 3 位都是 1 ，第 4 位为 0 表示它是一个 3 字节字符。\n下一个字节是开头为 10 的延续字节，这是正确的。\n但第二个延续字节不以 10 开头，所以是不符合规则的。\n
\n\n

 

\n\n

提示:

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