foo.c: In function 'Concat':
foo.c:6:9: warning: unused variable 'i' [-Wunused-variable]
    6 |     int i, lg;
      |         ^
foo.c: In function 'main':
foo.c:15:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
   15 |     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:16:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
   16 |     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:15:5: warning: ignoring return value of 'gets', declared with attribute warn_unused_result [-Wunused-result]
   15 |     gets(s1);
      |     ^~~~~~~~
foo.c:16:5: warning: ignoring return value of 'gets', declared with attribute warn_unused_result [-Wunused-result]
   16 |     gets(s2);
      |     ^~~~~~~~
/usr/bin/ld: /tmp/ccXBOEkW.o: in function `main':
foo.c:(.text.startup+0x4e): warning: the `gets' function is dangerous and should not be used.

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