CS211 Fall 2003 Prelim 2

Comments:


Problem 1:

1. explanations not relevant to the "real" reasons


Problem 2:

1. no typecasting for downcasting
2. not using inheritance
3. no getter methods
4. not checking for null
5. not setting left/right in constructor


Problem 3:

1. majority had trouble in part (c)
2. arguments for part (b) not strong enough


Problem 4:



Problem 5:

1. didn't check if string == null
2. didn't use recursion
3. code doesn't work for odd-lengthed string


Problem 6:

1. initialized each index in spine to point to empty ListCell's
2. didn't typecast correctly
3. incorrectly compared objects
4. didn't keep size variable
5. called methods on null objects