foo.c: In function 'Concat':
foo.c:7:12: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'int' [-Wformat=]
    7 |   printf("%s",s1[i]);
      |           ~^  ~~~~~
      |            |    |
      |            |    int
      |            char *
      |           %d
foo.c:11:12: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'int' [-Wformat=]
   11 |   printf("%s",s2[i]);
      |           ~^  ~~~~~
      |            |    |
      |            |    int
      |            char *
      |           %d
foo.c: In function 'main':
foo.c:18:3: warning: 'gets' is deprecated [-Wdeprecated-declarations]
   18 |   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:19:3: warning: 'gets' is deprecated [-Wdeprecated-declarations]
   19 |   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:18:3: warning: ignoring return value of 'gets', declared with attribute warn_unused_result [-Wunused-result]
   18 |   gets(s1);
      |   ^~~~~~~~
foo.c:19:3: warning: ignoring return value of 'gets', declared with attribute warn_unused_result [-Wunused-result]
   19 |   gets(s2);
      |   ^~~~~~~~
/usr/bin/ld: /tmp/ccq35dE3.o: in function `main':
foo.c:(.text.startup+0x4e): warning: the `gets' function is dangerous and should not be used.

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