foo.cc: In function 'std::ostream& operator<<(std::ostream&, Vector3Array&)':
foo.cc:84:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<Vector3>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   84 |   for(int i=0; i<c.Cs.size(); i++)
      |                ~^~~~~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:103:6: warning: unused variable 'x' [-Wunused-variable]
  103 |  int x,y,z;
      |      ^
foo.cc:103:8: warning: unused variable 'y' [-Wunused-variable]
  103 |  int x,y,z;
      |        ^
foo.cc:103:10: warning: unused variable 'z' [-Wunused-variable]
  103 |  int x,y,z;
      |          ^

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