Essential things to remember from today's class (class 18, 24th October)

Make sure you know how to handle files, both reading data from an existing
   one and creating and filling a new one.

Be fully familiar with the few basic string operations, +, comparisons <, >,
   <=, etc, s.length(), and what you get and can do by indexing: s[i].

Make sure you understand and could recreate the "manipulating strings"
   example.

Make sure you are familiar with the alternatives from <iomanip>, setw and
   setprecision.