foo.c: In function 'main':
foo.c:20:9: warning: 'gets' is deprecated [-Wdeprecated-declarations]
   20 |         gets(a);
      |         ^~~~
In file included from foo.c:1:
/nix/store/linb70pgp53f0kygxm5wk163dx22d681-glibc-2.37-45-dev/include/stdio.h:605:14: note: declared here
  605 | extern char *gets (char *__s) __wur __attribute_deprecated__;
      |              ^~~~
foo.c:21:9: warning: 'gets' is deprecated [-Wdeprecated-declarations]
   21 |         gets(b);
      |         ^~~~
/nix/store/linb70pgp53f0kygxm5wk163dx22d681-glibc-2.37-45-dev/include/stdio.h:605:14: note: declared here
  605 | extern char *gets (char *__s) __wur __attribute_deprecated__;
      |              ^~~~
foo.c: In function 'Diff':
foo.c:13:17: warning: 'n' may be used uninitialized [-Wmaybe-uninitialized]
   13 |         return N-n;
      |                ~^~
foo.c:4:15: note: 'n' was declared here
    4 |         int N,n,i=0;
      |               ^
foo.c:13:17: warning: 'N' may be used uninitialized [-Wmaybe-uninitialized]
   13 |         return N-n;
      |                ~^~
foo.c:4:13: note: 'N' was declared here
    4 |         int N,n,i=0;
      |             ^
/nix/store/3r87a2wq1w4l66wnsm7rqvy608mx23h6-binutils-2.40/bin/ld: /tmp/cc9gXIfD.o: in function `main':
foo.c:(.text.startup+0xb): warning: the `gets' function is dangerous and should not be used.

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