UTF8这个其实不改也没有问题，可以将给出的数组看成是多个字符的编码，然后判断是否合法，一下我的代码，改之前和之后都可以AC import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner in = new Scanner(System.in); String line = in.nextLine(); int N = Integer.parseInt(line); int code[] = new int[N]; String[] split = in.nextLine().split(" "); for(int i = 0; i < N; i++) { code[i] = (Integer.parseInt(split[i]) & 255); } int index = 0; int ret = 1; while(index != N && ret == 1) { if(code[index] <= 127) { index++; continue; } if(code[index] >= 192 && code[index] <= 223) { if(!(code[index + 1] >= 128 && code[index + 1] <= 191)) ret = 0; index += 2; continue; } if(code[index] >= 224 && code[index] <= 239) { if(!(code[index + 1] >= 128 && code[index + 1] <= 191 && code[index + 2] >= 128 && code[index + 2] <= 191)) ret = 0; index += 3; continue; } if(code[index] >= 240 && code[index] <= 247) { if(!(code[index + 1] >= 128 && code[index + 1] <= 191 && code[index + 2] >= 128 && code[index + 2] <= 191 && code[index + 3] >= 128 && code[index + 3] <= 191)) ret = 0; index += 4; continue; } ret = 0; } System.out.println(ret); } }