foo.cc: In function 'std::string H(std::string, std::string, int)':
foo.cc:12:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   12 |     for (int i = 0; i < b.size(); i++)
      |                     ~~^~~~~~~~~~
foo.cc:21:11: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   21 |         i < a.size() ? (a[i] += jw, jw = (a[i] - '0') / 10) : (a.push_back(jw + '0'), jw /= 10);
      |         ~~^~~~~~~~~~
foo.cc: In function 'std::string gwh(std::string)':
foo.cc:30:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   30 |     for (int i = 0; i < h.size(); i++)
      |                     ~~^~~~~~~~~~

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