foo.cc: In function 'void trans(std::string&)':
foo.cc:5:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    5 |     for(int i = 0;i < s.length();i++)
      |                   ~~^~~~~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:15:21: warning: comparison of integer expressions of different signedness: 'int' and 'const long unsigned int' [-Wsign-compare]
   15 |     for(int i = 0;i <= min(a.length(),b.length()); i++)
      |                   ~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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