What kind of algorithms are used to break down data? [closed]

It's difficult to tell what is being asked here. This question is ambiguous, vague, incomplete, overly broad, or rhetorical and cannot be reasonably answered in its current form. For help clarifying this question so that i开发者_StackOverflow社区t can be reopened, visit the help center. Closed 11 years ago.

I have a table with a large amount of data and need to do lookups on each and break down each of the data. Here's a simplified numeric example. I have this table:

1 [1]
2 [1, 1]
4 [2, 2]

now I want to break down 4. I look up and see 2+2=4. so then I look up 2 and see if breaks down into 1+1 so I know 2+1+1=4 and 1+1+1+1=4. For this problem, I should break it down(using the computed table) into 4 results(the 3 mentioned and 4 *1 =4).

I am not sure but is this a graph problem? or some other type? I think I can solve this by just using a recursions that break this down, but I want to learn if there's an general accepted way and this process will deal with large amounts of data so I'll need to design it in a way that the breakdown can be distributed over multiple CPUs.

Any idea what type of problem this is or the logic to solve it?

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As close as I can understand your specific example, it could be recursion, it could be a graph problem, it could be several other things, or a combination. Not every programming problem can be sorted into a single neat category, and there are generally at least a half-dozen different valid approaches to any problem.

In terms of dealing with large amounts of data specifically, there are many, many different strategies that may be employed, depending on how it needs to be accessed (sequentially? randomly by offset? randomly by key or some sort of search?), how frequently it will be updated, how much data there is in relationship to the sizes of the various levels of the storage hierarchy, etc.

And then there's multiple CPUs -- parallel processing -- where data synchronization becomes an important issue, in addition to the other problems.

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Your example is really too vague - you present it not as a real scenario or problem to be solved, but as an algorithm -

I look up and see 2+2=4. so then I look up 2 and see if breaks down into 1+1 so I know 2+1+1=4 and 1+1+1+1=4. For this problem, I should break it down(using the computed table) into 4 results(the 3 mentioned and 4 *1 =4).

You aren't asking how to do something - you're telling us what you want to do and asking the name of that activity.

From your question it's clear that you know what you need to do. Your process should be

• write the program to do whatever needs to be done
• if you get stuck at a particular point then research or ask a specific question
• and if it doesn't work or needs improvement then ask a specific question related to the problem area