foo.cc: In function 'void Output(std::vector<std::vector<int> >&)':
foo.cc:15:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   15 |         for(int i=0; i<M.size(); i++)
      |                      ~^~~~~~~~~
foo.cc:17:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   17 |                 for(int j=0; j<M[i].size(); j++)
      |                              ~^~~~~~~~~~~~
foo.cc: In function 'void Solve(std::vector<std::vector<int> >&, Loc, Loc, std::__cxx11::list<Loc>&)':
foo.cc:45:31: warning: comparison of integer expressions of different signedness: 'std::__cxx11::list<Loc>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   45 |                 if(path.size()<Min)
      |                    ~~~~~~~~~~~^~~~

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