foo.c: In function 'main':
foo.c:6:2: warning: 'gets' is deprecated [-Wdeprecated-declarations]
    6 |  gets(s1);
      |  ^~~~
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:7:2: warning: 'gets' is deprecated [-Wdeprecated-declarations]
    7 |  gets(s2);
      |  ^~~~
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:8:12: warning: array subscript has type 'char' [-Wchar-subscripts]
    8 |  for(i=0;s1[i]!='\0';i++)
      |            ^
foo.c:9:13: warning: array subscript has type 'char' [-Wchar-subscripts]
    9 |   for(n=0;s2[n]!='\0';n++)
      |             ^
foo.c:10:9: warning: array subscript has type 'char' [-Wchar-subscripts]
   10 |    if(s1[i]!=s2[n])
      |         ^
foo.c:10:16: warning: array subscript has type 'char' [-Wchar-subscripts]
   10 |    if(s1[i]!=s2[n])
      |                ^
foo.c:11:9: warning: array subscript has type 'char' [-Wchar-subscripts]
   11 |     s1[j++]=s1[i];
      |        ~^~
foo.c:11:15: warning: array subscript has type 'char' [-Wchar-subscripts]
   11 |     s1[j++]=s1[i];
      |               ^
foo.c:12:4: warning: array subscript has type 'char' [-Wchar-subscripts]
   12 |  s1[j]='\0';
      |    ^
foo.c:6:2: warning: ignoring return value of 'gets', declared with attribute warn_unused_result [-Wunused-result]
    6 |  gets(s1);
      |  ^~~~~~~~
foo.c:7:2: warning: ignoring return value of 'gets', declared with attribute warn_unused_result [-Wunused-result]
    7 |  gets(s2);
      |  ^~~~~~~~
/usr/bin/ld: /tmp/ccyppcO5.o: in function `main':
foo.c:(.text.startup+0x44): warning: the `gets' function is dangerous and should not be used.

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