foo.cc: In function 'void Count(char*, int*)':
foo.cc:6:22: warning: comparison of integer expressions of different signedness: 'int' and 'size_t' {aka 'long unsigned int'} [-Wsign-compare]
    6 |         for(int i=0;i<strlen(s);i++)
      |                     ~^~~~~~~~~~
foo.cc:11:30: warning: array subscript has type 'char' [-Wchar-subscripts]
   11 |                         a[s[i]]++;
      |                           ~~~^
foo.cc: In function 'int main()':
foo.cc:18:9: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
   18 |     gets(s);
      |     ~~~~^~~
In file included from foo.cc:1:
/nix/store/linb70pgp53f0kygxm5wk163dx22d681-glibc-2.37-45-dev/include/stdio.h:605:14: note: declared here
  605 | extern char *gets (char *__s) __wur __attribute_deprecated__;
      |              ^~~~
/nix/store/3r87a2wq1w4l66wnsm7rqvy608mx23h6-binutils-2.40/bin/ld: /tmp/ccMy2p6U.o: in function `main':
foo.cc:(.text.startup+0x35): warning: the `gets' function is dangerous and should not be used.

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