leetcode-daily/cpp/2203/220313-CN.cpp

38 lines
1.1 KiB
C++

#include <vector>
#include <iostream>
/**
* 393. UTF-8 Validation
* Given an integer array data representing the data, return whether it is a valid UTF-8 encoding.
* 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.
* 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.
*/
class Solution {
public:
static bool validUtf8(const std::vector<int>& data) {
int state = 0;
for (int i : data) {
if (state) {
if (i < 0x80 || i > 0xBF)
return false;
--state;
} else {
if (i < 0x80) continue;
for (int j = 0x80; i & j; j >>= 1)
++state;
if ((!--state) || (state > 3))
return false;
}
}
return state == 0;
}
};
int main() {
std::cout << Solution::validUtf8({235, 140, 4});
return 0;
}