foo.c: In function 'main':
foo.c:9:2: warning: 'gets' is deprecated [-Wdeprecated-declarations]
  gets(zfc);
  ^~~~
In file included from /usr/include/stdio.h:862:0,
                 from foo.c:1:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:232:1: note: declared here
 gets (char *__str)
 ^~~~
foo.c:19:11: warning: format '%d' expects argument of type 'int', but argument 2 has type 'long long int' [-Wformat=]
  printf("%d", ans);
          ~^
          %lld
foo.c:9:2: warning: ignoring return value of 'gets', declared with attribute warn_unused_result [-Wunused-result]
  gets(zfc);
  ^~~~~~~~~
/tmp/ccnewuXn.o: In function `main':
foo.c:(.text.startup+0x27): warning: the `gets' function is dangerous and should not be used.

[Hydro](https://hydro.ac)提供评测服务