foo.cc: In member function 'int BitSet::count()':
foo.cc:26:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   26 |         for (int i = 0; i < str.size(); i++)
      |                         ~~^~~~~~~~~~~~
foo.cc: In member function 'bool BitSet::any()':
foo.cc:35:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   35 |         for (int i = 0; i < str.size(); i++)
      |                         ~~^~~~~~~~~~~~

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