foo.cc: In copy constructor 'ComplexArray::ComplexArray(ComplexArray&)':
foo.cc:82:21: 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 < CA.C.size(); i++)
      |                   ~~^~~~~~~~~~~~~
foo.cc: In function 'std::ostream& operator<<(std::ostream&, ComplexArray&)':
foo.cc:96:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<Complex>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   96 |   for (int i = 0; i < CA.C.size(); i++)
      |                   ~~^~~~~~~~~~~~~
foo.cc: In function 'std::ostream& operator<<(std::ostream&, Complex&)':
foo.cc:55:2: warning: control reaches end of non-void function [-Wreturn-type]
   55 |  }
      |  ^

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