foo.c: In function 'main':
foo.c:16:2: warning: 'gets' is deprecated [-Wdeprecated-declarations]
   16 |  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:16:7: warning: passing argument 1 of 'gets' from incompatible pointer type [-Wincompatible-pointer-types]
   16 |  gets(s1);
      |       ^~
      |       |
      |       int *
In file included from /usr/include/stdio.h:867,
                 from foo.c:1:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:235:13: note: expected 'char *' but argument is of type 'int *'
  235 | gets (char *__str)
      |       ~~~~~~^~~~~
foo.c:17:2: warning: 'gets' is deprecated [-Wdeprecated-declarations]
   17 |  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:17:7: warning: passing argument 1 of 'gets' from incompatible pointer type [-Wincompatible-pointer-types]
   17 |  gets(s2);
      |       ^~
      |       |
      |       int *
In file included from /usr/include/stdio.h:867,
                 from foo.c:1:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:235:13: note: expected 'char *' but argument is of type 'int *'
  235 | gets (char *__str)
      |       ~~~~~~^~~~~
foo.c:18:9: warning: passing argument 1 of 'Concat' from incompatible pointer type [-Wincompatible-pointer-types]
   18 |  Concat(s1,s2);
      |         ^~
      |         |
      |         int *
foo.c:4:18: note: expected 'char *' but argument is of type 'int *'
    4 | void Concat(char str1[],char str2[])
      |             ~~~~~^~~~~~
foo.c:18:12: warning: passing argument 2 of 'Concat' from incompatible pointer type [-Wincompatible-pointer-types]
   18 |  Concat(s1,s2);
      |            ^~
      |            |
      |            int *
foo.c:4:30: note: expected 'char *' but argument is of type 'int *'
    4 | void Concat(char str1[],char str2[])
      |                         ~~~~~^~~~~~
foo.c:16:2: warning: ignoring return value of 'gets', declared with attribute warn_unused_result [-Wunused-result]
   16 |  gets(s1);
      |  ^~~~~~~~
foo.c:17:2: warning: ignoring return value of 'gets', declared with attribute warn_unused_result [-Wunused-result]
   17 |  gets(s2);
      |  ^~~~~~~~
/usr/bin/ld: /tmp/cchL5j87.o: in function `main':
foo.c:(.text.startup+0x4e): warning: the `gets' function is dangerous and should not be used.

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