C yes, C++ definitely not. C will help because it will introduce people to how things are actually stored in memory and because quite a few high level tools are implemented in C. C++ will just confuse the learner with excessive syntax.
Although at the same time, I find that C++ can be quite useful if you are disciplined in what parts of it you use.
I think it's great that you get some decent data structures (Standard Template Library) out of the box.
You can search for "malloc lab" and find tons of copies of the assignment (with only the instructor names and course numbers changed), but here's one:
http://www.cs.cmu.edu/afs/cs/academic/class/15213-f02/L6/mal...