/in/foo.c:1:1: error: unknown type name 'nt'; did you mean 'int'?
    1 | nt main() {
      | ^~
      | int
/in/foo.c: In function 'main':
/in/foo.c:3:9: error: expected expression before ':' token
    3 |     std::cout << "请输入整数 n 和要统计的数字 x：" << std::endl;
      |         ^
/in/foo.c:4:5: error: duplicate label 'std'
    4 |     std::cin >> n >> x;
      |     ^~~
/in/foo.c:3:5: note: previous definition of 'std' was here
    3 |     std::cout << "请输入整数 n 和要统计的数字 x：" << std::endl;
      |     ^~~
/in/foo.c:4:9: error: expected expression before ':' token
    4 |     std::cin >> n >> x;
      |         ^
/in/foo.c:7:9: error: duplicate label 'std'
    7 |         std::string str = std::to_string(i);
      |         ^~~
/in/foo.c:3:5: note: previous definition of 'std' was here
    3 |     std::cout << "请输入整数 n 和要统计的数字 x：" << std::endl;
      |     ^~~
/in/foo.c:7:13: error: expected expression before ':' token
    7 |         std::string str = std::to_string(i);
      |             ^
/in/foo.c:8:21: error: expected '=', ',', ';', 'asm' or '__attribute__' before ':' token
    8 |         for (char c : str) {
      |                     ^
/in/foo.c:9:17: error: 'c' undeclared (first use in this function)
    9 |             if (c - '0' == x) {
      |                 ^
/in/foo.c:9:17: note: each undeclared identifier is reported only once for each function it appears in
/in/foo.c:15:5: error: duplicate label 'std'
   15 |     std::cout << "数字 " << x << " 出现的次数为: " << num << std::endl;
      |     ^~~
/in/foo.c:3:5: note: previous definition of 'std' was here
    3 |     std::cout << "请输入整数 n 和要统计的数字 x：" << std::endl;
      |     ^~~
/in/foo.c:15:9: error: expected expression before ':' token
   15 |     std::cout << "数字 " << x << " 出现的次数为: " << num << std::endl;
      |         ^
/in/foo.c:3:5: warning: label 'std' defined but not used [-Wunused-label]
    3 |     std::cout << "请输入整数 n 和要统计的数字 x：" << std::endl;
      |     ^~~