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How many random elements before MD5 produces collisions?
... quintillion 374 quadrillion 607 trillion 431 billion 768 million 211 thousand 456.
However if you keep all the hashes then the probability is a bit higher thanks to birthday paradox. To have a 50% chance of any hash colliding with any other hash you need 264 hashes. This means that to get a collis...
How can I round a number in JavaScript? .toFixed() returns a string?
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It returns a string because 0.1, and powers thereof (which are used to display decimal fractions), are not representable (at least not with full accuracy) in binary floating-point systems.
For example, 0.1 is really 0.100000000000000005551115123125782702118...
versionCode vs versionName in Android Manifest
I had my app in the android market with version code = 2 and version name = 1.1
10 Answers
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IDEA: javac: source release 1.7 requires target release 1.7
...incorrect compiler options imported from Maven here:
Also check project and module bytecode (target) version settings outlined on the screenshot.
Other places where the source language level is configured:
Project Structure | Project
Project Structure | Modules (check every module) | Sour...
How to get Core Data object from specific Object ID?
...se comment.)
[eta.: Another important difference between the first method and the other two is that existingObjectWithID:error: never returns a fault; it always fetches the whole object for you. If you're trying to avoid that (e.g. working with an expensive-to-fetch object with a big blob property)...
Redis is single-threaded, then how does it do concurrent I/O?
...pends on how you define concurrency.
In server-side software, concurrency and parallelism are often considered as different concepts. In a server, supporting concurrent I/Os means the server is able to serve several clients by executing several flows corresponding to those clients with only one com...
What's a good way to overwrite DateTime.Now during testing?
... in providing the clock to the class that relies on it, but that could be handled by any number of dependency injection solutions (using an Inversion of Control container, plain old constructor/setter injection, or even a Static Gateway Pattern).
Other mechanisms of delivering an object or method t...
In Objective-C, how do I test the object type?
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If your object is myObject, and you want to test to see if it is an NSString, the code would be:
[myObject isKindOfClass:[NSString class]]
Likewise, if you wanted to test myObject for a UIImageView:
[myObject isKindOfClass:[UIImageView class]]
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Which letter of the English alphabet takes up most pixels?
...our environment. But the fact is, most fonts follow the same conventions, and capital W will be the widest.
Gist with these character widths in a ratio form (W = 100) captured here using this particular example font:
https://gist.github.com/imaurer/d330e68e70180c985b380f25e195b90c
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AWS S3: how do I see how much disk space is using
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AWS Cloudwatch now has a metric for bucket size and number of objects that is updated daily. About time! aws.amazon.com/blogs/aws/…
– cudds
Jul 28 '15 at 23:13
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