foo.cc: In function 'std::ostream& operator<<(std::ostream&, ComplexArray&)':
foo.cc:74:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<Complex>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   74 |   for(int i=0; i<c.Cs.size(); i++)
      |                ~^~~~~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:90:22: warning: unused variable 'r' [-Wunused-variable]
   90 |  ComplexArray ca;int r,i1;
      |                      ^
foo.cc:90:24: warning: unused variable 'i1' [-Wunused-variable]
   90 |  ComplexArray ca;int r,i1;
      |                        ^~
foo.cc: In function 'std::ostream& operator<<(std::ostream&, Complex&)':
foo.cc:26:2: warning: control reaches end of non-void function [-Wreturn-type]
   26 |  }
      |  ^

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