foo.c: In function 'main':
foo.c:56:9: warning: 'gets' is deprecated [-Wdeprecated-declarations]
   56 |         gets(s1);
      |         ^~~~
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:57:17: warning: format '%c' expects argument of type 'char *', but argument 2 has type 'int' [-Wformat=]
   57 |         scanf("%c",a);
      |                ~^  ~
      |                 |  |
      |                 |  int
      |                 char *
foo.c:57:9: warning: 'a' is used uninitialized [-Wuninitialized]
   57 |         scanf("%c",a);
      |         ^~~~~~~~~~~~~
foo.c:55:34: note: 'a' was declared here
   55 |         char s1[10000],s2[10000],a;
      |                                  ^
/nix/store/3r87a2wq1w4l66wnsm7rqvy608mx23h6-binutils-2.40/bin/ld: /tmp/ccVFDLHk.o: in function `main':
foo.c:(.text.startup+0xe): warning: the `gets' function is dangerous and should not be used.

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