foo.cc: In function 'std::vector<int> Index(std::string, int, std::string)':
foo.cc:15:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   15 |         while (i < s.length() && j < t.length())
      |                ~~^~~~~~~~~~~~
foo.cc:15:36: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   15 |         while (i < s.length() && j < t.length())
      |                                  ~~^~~~~~~~~~~~
foo.cc:28:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   28 |                 if (j == t.length())
      |                     ~~^~~~~~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:44:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   44 |         for (int i = 0; i < result.size(); i++)
      |                         ~~^~~~~~~~~~~~~~~
foo.cc:47:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   47 |                 if (i == result.size() - 1)
      |                     ~~^~~~~~~~~~~~~~~~~~~~

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