foo.c: In function 'main':
foo.c:6:2: warning: 'gets' is deprecated [-Wdeprecated-declarations]
    6 |  gets(a);
      |  ^~~~
In file included from /usr/include/stdio.h:867,
                 from foo.c:1:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:235:1: note: declared here
  235 | gets (char *__str)
      | ^~~~
foo.c:22:5: warning: statement with no effect [-Wunused-value]
   22 |     for (q; q < len; q++)
      |     ^~~
foo.c:18:3: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
   18 |   for (j = 0; j < len; j++)
      |   ^~~
foo.c:29:4: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
   29 |    len--;
      |    ^~~
foo.c:6:2: warning: ignoring return value of 'gets', declared with attribute warn_unused_result [-Wunused-result]
    6 |  gets(a);
      |  ^~~~~~~
foo.c:8:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    8 |  scanf("%c", &c);
      |  ^~~~~~~~~~~~~~~
/usr/bin/ld: /tmp/cc89BNaM.o: in function `main':
foo.c:(.text.startup+0x49): warning: the `gets' function is dangerous and should not be used.

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