foo.cc: In function 'int main()':
foo.cc:11:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   11 |         for(int i=0;i<s1.size();i++)
      |                     ~^~~~~~~~~~
foo.cc:14:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   14 |                 for(j=0;j<s2.size();j++)
      |                         ~^~~~~~~~~~
foo.cc:23:21: 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(j==s2.size())s++;
      |                    ~^~~~~~~~~~~

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