foo.cc: In function ‘int main()’:
foo.cc:37:21: warning: ‘char* gets(char*)’ is deprecated [-Wdeprecated-declarations]
   37 |                 gets(s);
      |                 ~~~~^~~
In file included from /nix/gcc-13.3.0/include/c++/13.3.0/cstdio:42,
                 from /nix/gcc-13.3.0/include/c++/13.3.0/ext/string_conversions.h:45,
                 from /nix/gcc-13.3.0/include/c++/13.3.0/bits/basic_string.h:4109,
                 from /nix/gcc-13.3.0/include/c++/13.3.0/string:54,
                 from /nix/gcc-13.3.0/include/c++/13.3.0/bitset:52,
                 from stdc++.h:52:
/nix/glibc-2.40-66-dev/include/stdio.h:667:14: note: declared here
  667 | extern char *gets (char *__s) __wur __attribute_deprecated__;
      |              ^~~~
foo.cc:43:7: warning: this ‘if’ clause does not guard... [-Wmisleading-indentation]
   43 |       if(bz[i][j])
      |       ^~
foo.cc:45:9: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the ‘if’
   45 |         printf("%d",num);
      |         ^~~~~~
foo.cc:30:21: warning: unused variable ‘ch’ [-Wunused-variable]
   30 |         char s[100],ch;
      |                     ^~
/nix/binutils-2.43.1/bin/ld: /tmp/ccrWMPjW.o: in function `main':
foo.cc:(.text.startup+0xb4): warning: the `gets' function is dangerous and should not be used.