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).
A character in UTF8 can be from 1 to 4 bytes long, subjected to the following rules:
\n\n0, followed by its Unicode code.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.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.
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\n1 <= data.length <= 2 * 1040 <= data[i] <= 255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。
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这是 UTF-8 编码的工作方式：
\n\n\n Char. number range | UTF-8 octet sequence\n (hexadecimal) | (binary)\n --------------------+---------------------------------------------\n 0000 0000-0000 007F | 0xxxxxxx\n 0000 0080-0000 07FF | 110xxxxx 10xxxxxx\n 0000 0800-0000 FFFF | 1110xxxx 10xxxxxx 10xxxxxx\n 0001 0000-0010 FFFF | 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx\n\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:
\n\n1 <= data.length <= 2 * 1040 <= data[i] <= 255\r\nmask = 1 << 7\r\nwhile mask & num:\r\n n_bytes += 1\r\n mask = mask >> 1\r\n\r\n\r\nCan you use bit-masking to perform the second validation as well i.e. checking if the most significant bit is 1 and the second most significant bit a 0?", "To check if the most significant bit is a 1 and the second most significant bit is a 0, we can make use of the following two masks.\r\n\r\n
\r\nmask1 = 1 << 7\r\nmask2 = 1 << 6\r\n\r\nif not (num & mask1 and not (num & mask2)):\r\n return False\r\n" ], "solution": null, "status": null, "sampleTestCase": "[197,130,1]", "metaData": "{\r\n \"name\": \"validUtf8\",\r\n \"params\": [\r\n {\r\n \"name\": \"data\",\r\n \"type\": \"integer[]\"\r\n }\r\n ],\r\n \"return\": {\r\n \"type\": \"boolean\"\r\n }\r\n}", "judgerAvailable": true, "judgeType": "large", "mysqlSchemas": [], "enableRunCode": true, "envInfo": "{\"cpp\":[\"C++\",\"
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