It is a difficult job to schedule all of the courses in a university to
satisfy students' choices with a minimum of conflicts. The task is made
all the more difficult when some students don't pre-enroll,
or pre-enroll multiple times because they forget that they
already did it.
The first line of input contains an integer
0 < n <= 100000,
the number of student course requests.
Each of the next n lines
contains three strings separated by spaces: a student's first and
last name, and the course that the student wishes to take.
You may assume that each name is a string of at least one and at
most 20 upper-case letters, and that a course is a string of at
least one and at most 10 upper-case letters and digits.
If a student requests a given course more than once, only the
first such request should be considered. You may assume that
no two students have both their first and last names the same.
PINK TIE CS241
For each requested course, output a line containing the course, a space,
and the number of students who requested the course. Output the
courses sorted in lexicographical order (with digits sorted before letters).
Output for Sample Input