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:18:50: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   18 |                         while (s1[j] == s2[k]&& j<s1.size() && k < s2.size())
      |                                                 ~^~~~~~~~~~
foo.cc:18:66: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   18 |                         while (s1[j] == s2[k]&& j<s1.size() && k < s2.size())
      |                                                                ~~^~~~~~~~~~~
foo.cc:23:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   23 |                         if (k == s2.size())
      |                             ~~^~~~~~~~~~~~
foo.cc:10:13: warning: unused variable 's' [-Wunused-variable]
   10 |         int s=0;
      |             ^

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