Problem Statement:

Calculate the number of sessions (valid and total) of a game and the average session time(only valid) from the given dataset and explain your calculation strategy.

Description:

At GreedyGame, one of the user behaviour metrics is the Gaming Session. These are calculated based on the events that are sent out by our Mobile SDK. A gaming session happens when a user plays a game on a device (identified by ‘ai5’ field). The following are some attributes of a session.

1. A session typically starts with a GGSTART event

2. A session typically ends with a GGSTOP event.

3. If there is a time difference of more than 30 secs between a GGSTOP and GGSTART, they are considered to be different sessions.

4. There can be multiple GGSTART and GGSTOP calls in a single session.

5. If a session is more than 60 seconds long, it is classified as a valid session.

6. If a session is less than 1 second, it should be ignored

7. Incase of multiple GGSTART and GGSTOP calls, the exact time of the session should be taken for establishing session validity (not the difference between the first GGSTART and the last GGSTOP call)

To understand this functionality better, consider the following sequence of calls for a particular

ggstart 2016­05­09 2:00:00

ggstop 2016­05­09 2:09:13

ggstart 2016­05­09 2:09:14

ggstop 2016­05­09 2:17:57

ggstart 2016­05­09 3:00:00

ggstop 2016­05­09 3:02:46

If you look at the data above, this represents two sessions (first one from 2:00:00 to 2:17:57, with a total time of 17:56 and the second one from 3:00:00 to 3:02:46 with a total time of 2:46) Because of the nature of mobile data, there are bound to be data losses in the entries. The algorithm should take this into account when figuring out sessions and work with a minimum loss strategy.

You are free to choose a language to tackle the problem.