foo.cc: In function 'int main()':
foo.cc:14:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   14 |     while (pos < sentence.length())
      |            ~~~~^~~~~~~~~~~~~~~~~~~
foo.cc:17:22: warning: comparison of integer expressions of different signedness: 'int' and 'const std::__cxx11::basic_string<char>::size_type' {aka 'const long unsigned int'} [-Wsign-compare]
   17 |         if (find_pos == string::npos) break;
      |             ~~~~~~~~~^~~~~~~~~~~~~~~

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