UTF-8 Validation

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:

For a 1-byte character, the first bit is a 0 , followed by its Unicode code.

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 .

This is how the UTF-8 encoding would work:

Number of Bytes | UTF-8 Octet Sequence

--------------------+-----------------------------------------

1 | 0xxxxxxx

2 | 110xxxxx 10xxxxxx

3 | 1110xxxx 10xxxxxx 10xxxxxx

4 | 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx

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.