foo.cc: In function 'int main()':
foo.cc:12:13: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
   gets(ch[i]);
             ^
In file included from /usr/include/c++/7/cstdio:42:0,
                 from foo.cc:1:
/usr/include/stdio.h:638:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
foo.cc:10:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d\n",&n);
  ~~~~~^~~~~~~~~~~
foo.cc:12:7: warning: ignoring return value of 'char* gets(char*)', declared with attribute warn_unused_result [-Wunused-result]
   gets(ch[i]);
   ~~~~^~~~~~~
/tmp/ccos1nSu.o: In function `main':
foo.cc:(.text.startup+0x4b): warning: the `gets' function is dangerous and should not be used.

自豪的采用 HydroJudge 进行评测(github.com/hydro-dev/HydroJudge)

{"receive":"2020-08-10T08:41:36.579Z","handle":"2020-08-10T08:41:36.579Z","cache_start":"2020-08-10T08:41:36.587Z","read_cases":"2020-08-10T08:41:36.698Z","judge":"2020-08-10T08:41:36.699Z","done":"2020-08-10T08:41:37.106Z"}