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What is an NP-complete in computer science?
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NP stands for Non-deterministic Polynomial time.
This means that the problem can be solved in Polynomial time using a Non-deterministic Turing machine (like a regular Turing machine but also including a non-deterministic "choice"...
Cannot create an NSPersistentStoreCoordinator with a nil model
Been having my first crack at Core Data and I'm getting the following error when running my code on my device, but it works fine on the simulator..
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Android Studio needs JDK 7 for Android-L mac
I was trying to look how my app looks in material design and I would like to use the new cards lib.
My Problem is, that it's giving me this error within my gradle file and I need to fix that.
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Simulator or Emulator? What is the difference?
While I understand what simulation and emulation mean in general, I almost always get confused about them. Assume that I create a piece of software that mimics existing hardware/software, what should I call it? A simulator or an emulator?
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Sleeping in a batch file
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UPDATE
The timeout command, available from Windows Vista and onwards should be the command used, as described in another answer to this question. What follows here is an old answer.
Old answer
If you have Python installed, or don't mind installing...
Using Transactions or SaveChanges(false) and AcceptAllChanges()?
I have been investigating transactions and it appears that they take care of themselves in EF as long as I pass false to SaveChanges() and then call AcceptAllChanges() if there are no errors:
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node.js child process - difference between spawn & fork
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Spawn is a command designed to run system commands. When you run spawn, you send it a system command that will be run on its own process, but does not execute any further code within your node process. You can add listeners for the proces...
How do I “Add Existing Item” an entire directory structure in Visual Studio?
I have a free standing set of files not affiliated with any C# project at all that reside in a complicated nested directory structure.
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Confusion: @NotNull vs. @Column(nullable = false) with JPA and Hibernate
...tation of JSR 303, however, it intelligently picks up on these constraints and translates them into database constraints for you, so you get two for the price of one. @Column(nullable = false) is the JPA way of declaring a column to be not-null. I.e. the former is intended for validation and the lat...
Listing only directories using ls in Bash?
This command lists directories in the current path: ls -d */
26 Answers
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