acm-contest

Last year there were a lot of complaints concerning the set of problems. Most contestants considered our problems to be too hard to solve. One reason for this is that the team members responsible for the problems are not able to evaluate properly whether a particular problem is easy or hard to solve. (We have created until now so many problems, that all seems quite easy.) Because we want our future contests to be better we would like to be able to evaluate the hardness of our problems after the contest using a history of submissions.

There are a few statistics that we can use for evaluating the hardness of a particular problem: the number of accepted solutions of the problem, the average number of submissions of the problem and the average time consumed to solve it (as "General rules" of the contest state "the time consumed for a solved problem is the time elapsed from the beginning of the contest to the submittal of the accepted run"). For the latter two statistics we consider only the teams which solved this particular problem.

Needless to say we ask you to write a program that computes aforementioned statistics for all problems.

Task Write a program that:

- reads a history of submissions during an ACM contest,
- computes for each problem the number of accepted solutions of the problem, the average number of submissions and the average time consumed to solve it,
- writes the result.