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How does Duff's device work?
I've read the article on Wikipedia on the Duff's device , and I don't get it. I am really interested, but I've read the explanation there a couple of times and I still don't get it how the Duff's device works.
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Use RSA private key to generate public key?
I don't really understand this one:
9 Answers
9
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Facebook database design?
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Keep a friend table that holds the UserID and then the UserID of the friend (we will call it FriendID). Both columns would be foreign keys back to the Users table.
Somewhat useful example:
Table Name: User
Columns:
UserID PK
EmailAddress
Password
Ge...
What is the best way to get all the divisors of a number?
...e dumb way (stopping at n/2) very cool, thank you!
– Andrea Ambu
Oct 5 '08 at 10:20
47
For those ...
Storing sex (gender) in database
... 2,147,483,648 to 2,147,483,647
BIT 1 (2 if 9+ columns) 2 (0 and 1)
CHAR(1) 1 26 if case insensitive, 52 otherwise
The BIT data type can be ruled out because it only supports two possible genders which is inadequate. While INT supports more than two options, i...
Why is “int i = 2147483647 + 1;” OK, but “byte b = 127 + 1;” is not compilable?
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Constants are evaluated as ints, so 2147483647 + 1 overflows and gives you a new int, which is assignable to int, while 127 + 1 also evaluated as int equals to 128, and it is not assignable to byte.
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How to update Ruby to 1.9.x on Mac?
I have created a new user account on my mac and I am trying to update to the current version of ruby on it (1.9.2) from the snow leopard default of 1.8.7. Can somebody point me to tutorial or explain the best method to update Ruby on my mac from 1.8 to 1.9.2? Thanks
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Apache Spark: The number of cores vs. the number of executors
I'm trying to understand the relationship of the number of cores and the number of executors when running a Spark job on YARN.
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List of lists changes reflected across sublists unexpectedly
...(3)]
which will reevaluate [1]*4 each time instead of evaluating it once and making 3 references to 1 list.
You might wonder why * can't make independent objects the way the list comprehension does. That's because the multiplication operator * operates on objects, without seeing expressions. Wh...
Xcode 6 beta 2 issue exporting .ipa: “Your account already has a valid iOS distribution certificate”
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This is what worked for me.
On my machine I kept both Xcode 5 and Xcode 6 beta.
From Xcode 6 beta, Archive the project. Close Xcode 6.
Open Xcode 5, go to Organizer and export as Ad Hoc build with proper provisioning profile.
That's it!
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