foo.c: In function 'main':
foo.c:5:1: warning: 'gets' is deprecated [-Wdeprecated-declarations]
    5 | gets(s);
      | ^~~~
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:19:7: warning: multi-character character constant [-Wmultichar]
   19 |  s[i]='/0';
      |       ^~~~
foo.c:19:7: warning: overflow in conversion from 'int' to 'char' changes value from '12080' to '48' [-Woverflow]
foo.c:5:1: warning: ignoring return value of 'gets', declared with attribute warn_unused_result [-Wunused-result]
    5 | gets(s);
      | ^~~~~~~
foo.c:9:1: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    9 | scanf("%d%d",&s1,&len);
      | ^~~~~~~~~~~~~~~~~~~~~~
/usr/bin/ld: /tmp/cc5459zy.o: in function `main':
foo.c:(.text.startup+0x33): warning: the `gets' function is dangerous and should not be used.

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