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\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
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