foo.c: In function 'main':
foo.c:8:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
     gets(a);
     ^~~~
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:65:10: warning: passing argument 1 of 'printf' makes pointer from integer without a cast [-Wint-conversion]
   printf(' ');
          ^~~
In file included from /usr/include/stdio.h:862:0,
                 from foo.c:1:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:102:1: note: expected 'const char * restrict' but argument is of type 'int'
 printf (const char *__restrict __fmt, ...)
 ^~~~~~
foo.c:65:3: warning: format not a string literal and no format arguments [-Wformat-security]
   printf(' ');
   ^~~~~~
foo.c:8:5: warning: ignoring return value of 'gets', declared with attribute warn_unused_result [-Wunused-result]
     gets(a);
     ^~~~~~~
/tmp/cchyEdyq.o: In function `main':
foo.c:(.text.startup+0x43): warning: the `gets' function is dangerous and should not be used.

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