foo.cc: In function 'int main()':
foo.cc:12:31: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'll' {aka 'long long int'} [-Wsign-compare]
   12 |                 if(s[j].size()<mi)
      |                    ~~~~~~~~~~~^~~

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