foo.c: In function 'main':
foo.c:8:30: error: invalid suffix "；" on integer constant
    8 |                 sum += num % 10；
      |                              ^~~~
foo.c:8:34: error: expected ';' before 'num'
    8 |                 sum += num % 10；
      |                                  ^
      |                                  ;
    9 |                 num /= 10;
      |                 ~~~               
foo.c:11:18: warning: format '%d' expects a matching 'int' argument [-Wformat=]
   11 |         printf("%d\n, sum");
      |                 ~^
      |                  |
      |                  int
foo.c:5:14: warning: variable 'sum' set but not used [-Wunused-but-set-variable]
    5 |     int num, sum = 0;
      |              ^~~

[Hydro](https://hydro.ac)提供评测服务