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What is a plain English explanation of “Big O” notation?
I'd prefer as little formal definition as possible and simple mathematics.
41 Answers
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Converting PKCS#12 certificate into PEM using OpenSSL
...as file:
p12 = crypto.load_pkcs12(file.read(), "my_passphrase")
# PEM formatted private key
print crypto.dump_privatekey(crypto.FILETYPE_PEM, p12.get_privatekey())
# PEM formatted certificate
print crypto.dump_certificate(crypto.FILETYPE_PEM, p12.get_certificate())
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How to convert milliseconds to “hh:mm:ss” format?
...ILLISECONDS.toMinutes(millis)));
System.out.println(hms);
}
Output:
01:00:00
I realised that my code above can be greatly simplified by using a modulus division instead of subtraction:
String hms = String.format("%02d:%02d:%02d", TimeUnit.MILLISECONDS.toHours(millis),
TimeUnit.MILLIS...
Calculate difference between two dates (number of days)?
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this will return 1 less days, 08/31/2013-08/01/2013=31 but this is returning 30 only.
– J R B
Aug 7 '13 at 8:13
62
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How can you dynamically create variables via a while loop? [duplicate]
...dictionaries, but that's normally not noticeable in any way (except for performance), and it may change in the future. Examples of namespaces are: the set of built-in names (functions such as abs(), and built-in exception names); the global names in a module; and the local names in a function invoca...
Json.net serialize/deserialize derived types?
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This doesn't work when deserialization is performed on another solution/project. On serialization the name of the Solution is embedded within as type: "SOLUTIONNAME.Models.Model". On deserialization on the other solution it will throw "JsonSerializationException: Could ...
In javascript, is an empty string always false as a boolean?
...w String("") is truthy! This is because it is an object, whereas the short form "" represents the primitive value version. The same goes for new Number(0) and even new Boolean(false). It's a good reason not to use the object versions in your code, and it does mean that if (str.length) handles this e...
Django FileField with upload_to determined at runtime
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Does this work with ModelForm? I can see that instance has all the attributes of the class model, but there are no values (just a str of the field name). In the template, user is hidden. I may have to submit a question, I have been googling this f...
Why exactly is eval evil?
...oblems are. I see now from the answers here what they are (security and performance problems).
– Jay
Apr 3 '10 at 14:21
8
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Finding the average of a list
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HermsHerms
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