foo.cc: In function 'std::ostream& operator<<(std::ostream&, ComplexArray&)':
foo.cc:82:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<Complex>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   82 |         for(int i=0;i<c.Cs.size();i++)
      |                     ~^~~~~~~~~~~~
foo.cc: In function 'std::ostream& operator<<(std::ostream&, Complex&)':
foo.cc:30:5: warning: control reaches end of non-void function [-Wreturn-type]
   30 |     }
      |     ^

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