foo.c: In function 'main':
foo.c:11:2: warning: 'gets' is deprecated [-Wdeprecated-declarations]
   11 |  gets(a);
      |  ^~~~
In file included from /usr/include/stdio.h:867,
                 from foo.c:2:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:235:1: note: declared here
  235 | gets (char *__str)
      | ^~~~
foo.c:8:9: warning: unused variable 'o' [-Wunused-variable]
    8 |  int n, o = 0;
      |         ^
foo.c:10:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   10 |  scanf("%d ", &n);
      |  ^~~~~~~~~~~~~~~~
foo.c:11:2: warning: ignoring return value of 'gets', declared with attribute warn_unused_result [-Wunused-result]
   11 |  gets(a);
      |  ^~~~~~~
/usr/bin/ld: /tmp/ccWHC3Tr.o: in function `main':
foo.c:(.text.startup+0x47): warning: the `gets' function is dangerous and should not be used.

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