2015 AP CS A Exam Free Response Solutions

The 2015 AP Computer Science A Free Response problems are of roughly average difficulty.

The DiverseArray method rowSums requires treating a 2D array as an array of 1D arrays.

Implementing the HiddenWord class requires appropriate use of String class methods.

The SparseArray problem initially appears to feature a 2D array, but actually features an ArrayList. Understanding what the elements in the list represent is critical.

The NumberGroup problem requires writing, implementing, and using a simple interface.