foo.cc: In function 'bool part(std::string&, std::string&)':
foo.cc:26:34: 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, j = 0; j < b.size(); j++)
      |                                ~~^~~~~~~~~~
foo.cc:27:41: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   27 |                 if (b[j] == a[i] && ++i == a.size())
      |                                     ~~~~^~~~~~~~~~~

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