foo.c:3:23: error: unknown type name 'ch2'
    3 | void Count(char ch1[],ch2[])
      |                       ^~~
foo.c: In function 'main':
foo.c:19:2: warning: 'gets' is deprecated [-Wdeprecated-declarations]
   19 |  gets(c1);
      |  ^~~~
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:20:2: warning: 'gets' is deprecated [-Wdeprecated-declarations]
   20 |  gets(c2);
      |  ^~~~
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:21:2: warning: implicit declaration of function 'Count' [-Wimplicit-function-declaration]
   21 |  Count(c1,c2);
      |  ^~~~~
foo.c:19:2: warning: ignoring return value of 'gets', declared with attribute warn_unused_result [-Wunused-result]
   19 |  gets(c1);
      |  ^~~~~~~~
foo.c:20:2: warning: ignoring return value of 'gets', declared with attribute warn_unused_result [-Wunused-result]
   20 |  gets(c2);
      |  ^~~~~~~~

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