foo.cc: In function 'int main()':
foo.cc:12:27: 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 < s1.size(); i++)
      |                         ~~^~~~~~~~~~~
foo.cc:17:57: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   17 |                         while (s1[i + j] == s2[j]&&i + j<s1.size() && j < s2.size())
      |                                                    ~~~~~^~~~~~~~~~
foo.cc:17:73: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   17 |                         while (s1[i + j] == s2[j]&&i + j<s1.size() && j < s2.size())
      |                                                                       ~~^~~~~~~~~~~
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 == s2.size())
      |                             ~~^~~~~~~~~~~~

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