foo.c: In function 'main':
foo.c:10:2: warning: 'gets' is deprecated [-Wdeprecated-declarations]
   10 |  gets(str1);
      |  ^~~~
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:11:2: warning: 'gets' is deprecated [-Wdeprecated-declarations]
   11 |  gets(str2);
      |  ^~~~
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:9:7: warning: unused variable 'ch' [-Wunused-variable]
    9 |  char ch;
      |       ^~
foo.c:8:8: warning: unused variable 'p2' [-Wunused-variable]
    8 |  char *p2 = str2;
      |        ^~
foo.c:6:8: warning: unused variable 'p1' [-Wunused-variable]
    6 |  char *p1 = str1;
      |        ^~
foo.c:10:2: warning: ignoring return value of 'gets', declared with attribute warn_unused_result [-Wunused-result]
   10 |  gets(str1);
      |  ^~~~~~~~~~
foo.c:11:2: warning: ignoring return value of 'gets', declared with attribute warn_unused_result [-Wunused-result]
   11 |  gets(str2);
      |  ^~~~~~~~~~
/usr/bin/ld: /tmp/ccX9VyEL.o: in function `main':
foo.c:(.text.startup+0x4e): warning: the `gets' function is dangerous and should not be used.

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