Compile Errors: - forgot to include "section5a.h" in section5a.cc - forgot to put an end curly brace and semicolon at the end of section5a.h - the "friend" specifier should only be inside the class declaration (section5a.h), not in the definition (section5a.cc) - resize needs to be declared in the header (as a private method) - operator[] had a signed/unsigned mismatch Correctness Errors: - in op<<, the entire for loop needs to be wrapped in the if clause - in op<<, need to print arr_[i], not arr_ - memcpy needs to be len * sizeof(int) - capacity and len should be unsigned to prevent negative values Additional Notes: - added some consts - technically resize should check that cap is larger than or equal to capacity_, but it's an internal function so we can more or less get away with saying that it's a precondition - the len getter can be defined inline