SortedSet<Student> enrolled;

foreach (Student slacker in enrolled)
// ....

Dictionary<string, int> slacker;

map<string, int> mapOfStuff;
// the mapOfStuff contains pairs that look like the one below
Pair<string, int> pairs;

foreach (KeyValuePair<string, int> i in slacker)
{
  Console.WriteLine(String.Format("This key {0} is paired with this value {1}",
                    i.Key, i.Value));
}