foo.cc: In function 'int main()':
foo.cc:10:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   10 |         for (int i = 0; i < s.length(); i++) {
      |                         ~~^~~~~~~~~~~~
foo.cc:14:34: 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 (j < t.length()) {
      |                                ~~^~~~~~~~~~~~
foo.cc:21:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   21 |                         if (j == t.length())
      |                             ~~^~~~~~~~~~~~~

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