foo.cc: In member function 'void Array::putout()':
foo.cc:16:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   16 |         for (int i = 0; i < arr.size(); ++i) {
      |                         ~~^~~~~~~~~~~~
foo.cc: In member function 'void Array::deleteAT(int)':
foo.cc:24:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   24 |         if(ii >= 0 && ii < arr.size()) {
      |                       ~~~^~~~~~~~~~~~

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