foo.cc: In function 'int main()':
foo.cc:43:34: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   43 |                 for(int i = 0; i < res.size(); i ++)
      |                                ~~^~~~~~~~~~~~
foo.cc:42:11: warning: suggest explicit braces to avoid ambiguous 'else' [-Wdangling-else]
   42 |         if(!flag)
      |           ^
foo.cc:35:17: warning: 'num' may be used uninitialized [-Wmaybe-uninitialized]
   35 |         if(num[n]) res += 'w';
      |            ~~~~~^
foo.cc:16:13: note: 'num' declared here
   16 |         int num[100000];
      |             ^~~

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