foo.cc: In function 'int main()':
foo.cc:8:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    8 |         for(int i=0;i<aa.size();i++)
      |                     ~^~~~~~~~~~
foo.cc:10:22: 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<bb.size();i++)
      |                     ~^~~~~~~~~~
foo.cc:14:22: warning: comparison of integer expressions of different signedness: 'int' and 'const long unsigned int' [-Wsign-compare]
   14 |         for(int i=0;i<max(aa.size(),bb.size());i++)
      |                     ~^~~~~~~~~~~~~~~~~~~~~~~~~
foo.cc:20:22: warning: comparison of integer expressions of different signedness: 'int' and 'const long unsigned int' [-Wsign-compare]
   20 |         for(int i=0;i<max(aa.size(),bb.size());i++)
      |                     ~^~~~~~~~~~~~~~~~~~~~~~~~~

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