DWITE 2008-10, 2008-11, 2008-12, 2009-01, 2009-02, 2011-07, 2012-10, 2012-11, 2013-02: Made minor edits to problem statements - for wording, grammar, punctuation, formatting.
DWITE 2011-10 P4: Rewrote code, added explanation.
DWITE 2008-10 P5, 2011-07 P3, 2012-01 P2: Tweaked code.