Feedback for A2 part a
----------------------

- Generally speaking, those who submitted some working code appear to
  be on the right track.

- Some of you have designed your BST so that the entire tree is in memory.
  You are not allowed to use such a design for this assignment as the handout
  specifies that the index cannot fit into memory.

- When using C-style strings (i.e. char arrays), be careful about memory
  allocation. For example, when using strcat(s1, s2), the array pointed to
  by s1 must already be large enought to hold the concatenated string,
  including the null terminator. Here is some code that won't work:

  char s1[10] = "hello";
  char s2[10] = "world";

  strcat(s1, s2);

  In the above example, the concatenated string has size 11 (including the
  null terminator), and so s1 is not large enough. If you are having trouble
  using C-style strings you might want to try using the C++ string class.

- Many of you did not sumbit any test runs. Testing was also an area of
  weakness in A1 part b. I would suggest re-reading the document on testing
  that is posted on the main page of the course website.


--Ali