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:9:25: warning: unused variable 'n' [-Wunused-variable]
    9 |  int i = 0, j, k, l, m, n;
      |                         ^
foo.c:9:22: warning: unused variable 'm' [-Wunused-variable]
    9 |  int i = 0, j, k, l, m, n;
      |                      ^
foo.c:9:19: warning: unused variable 'l' [-Wunused-variable]
    9 |  int i = 0, j, k, l, m, n;
      |                   ^
foo.c:9:16: warning: unused variable 'k' [-Wunused-variable]
    9 |  int i = 0, j, k, l, m, n;
      |                ^
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", &b);
      |  ^~~~~~~~~~~~~~~
/usr/bin/ld: /tmp/ccf2gAuU.o: in function `main':
foo.c:(.text.startup+0x2a): warning: the `gets' function is dangerous and should not be used.

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