In the cinema business, a feature film is usually provided to a regional distributor based on a contract for exhibition in a particular geographical territory.
Each authorization is specified by a combination of included and excluded regions. For example, a distributor might be authorzied in the following manner:
Permissions for DISTRIBUTOR1
INCLUDE: INDIA
INCLUDE: UNITEDSTATES
EXCLUDE: KARNATAKA-INDIA
EXCLUDE: CHENNAI-TAMILNADU-INDIA
This allows DISTRIBUTOR1 to distribute in any city inside the United States and India, except cities in the state of Karnataka (in India) and the city of Chennai (in Tamil Nadu, India).
At this point, asking your program if DISTRIBUTOR1 has permission to distribute in CHICAGO-ILLINOIS-UNITEDSTATES should get YES as the answer, and asking if distribution can happen in CHENNAI-TAMILNADU-INDIA should of course be NO. Asking if distribution is possible in BANGALORE-KARNATAKA-INDIA should also be NO, because the whole state of Karnataka has been excluded.
Sometimes, a distributor might split the work of distribution amount smaller sub-distiributors inside their authorized geographies. For instance, DISTRIBUTOR1 might assign the following permissions to DISTRIBUTOR2:
Permissions for DISTRIBUTOR2 < DISTRIBUTOR1
INCLUDE: INDIA
EXCLUDE: TAMILNADU-INDIA
Now, DISTRIBUTOR2 can distribute the movie anywhere in INDIA, except inside TAMILNADU-INDIA and KARNATAKA-INDIA - DISTRIBUTOR2's permissions are always a subset of DISTRIBUTOR1's permissions. It's impossible/invalid for DISTRIBUTOR2 to have INCLUDE: CHINA, for example, because DISTRIBUTOR1 isn't authorized to do that in the first place.
If DISTRIBUTOR2 authorizes DISTRIBUTOR3 to handle just the city of Hubli, Karnataka, India, for example:
Permissions for DISTRIBUTOR3 < DISTRIBUTOR2 < DISTRIBUTOR1
INCLUDE: HUBLI-KARNATAKA-INDIA
Again, DISTRIBUTOR2 cannot authorize DISTRIBUTOR3 with a region that they themselves do not have access to.
We've provided a CSV with the list of all countries, states and cities in the world that we know of - please use the data mentioned there for this program. The codes you see there may be different from what you see here, so please always use the codes in the CSV. This Readme is only an example.
Write a program in any language you want (If you're here from Gophercon, use Go :D) that does this. Feel free to make your own input and output format / command line tool / GUI / Webservice / whatever you want. Feel free to hold the dataset in whatever structure you want, but try not to use external databases - as far as possible stick to your langauage without bringing in MySQL/Postgres/MongoDB/Redis/Etc.
To submit a solution, fork this repo and send a Pull Request on Github.
For any questions or clarifications, raise an issue on this repo and we'll answer your questions as fast as we can.
