foo.cc: In function 'int main()':
foo.cc:11:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   11 |     for (int i = 0; i < str.length(); i++)
      |                     ~~^~~~~~~~~~~~~~
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.length(); i++)
      |                         ~~^~~~~~~~~~~~~~
foo.cc:38:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   38 |         for (int i = 0; i < str.length(); i++)
      |                         ~~^~~~~~~~~~~~~~
foo.cc:51:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   51 |         for (int i = 0; i < str.length(); i++)
      |                         ~~^~~~~~~~~~~~~~
foo.cc:60:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   60 |         for (int i = 0; i < str.length(); i++)
      |                         ~~^~~~~~~~~~~~~~

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