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If strings are immutable in .NET, then why does Substring take O(n) time?
... liked this question so much, I just blogged it. See Strings, immutability and persistence
The short answer is: O(n) is O(1) if n does not grow large. Most people extract tiny substrings from tiny strings, so how the complexity grows asymptotically is completely irrelevant.
The long answer is:
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MySQL Insert Where query
...ySQL INSERT Syntax does not support the WHERE clause so your query as it stands will fail. Assuming your id column is unique or primary key:
If you're trying to insert a new row with ID 1 you should be using:
INSERT INTO Users(id, weight, desiredWeight) VALUES(1, 160, 145);
If you're trying to c...
How does OpenID authentication work?
...e of already existing internet technology (URI, HTTP, SSL, Diffie-Hellman) and realizes that people are already creating identities for themselves whether it be at their blog, photostream, profile page, etc. With OpenID you can easily transform one of these existing URIs into an account which can be...
Open file dialog box in JavaScript
... <input type='file' /> control itself. But a div is placed over that and css styles are applied to get that feel. Opacity of the file control is set to 0 so that it appears that the dialog window is opened when clicking on the div.
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Can you change a path without reloading the controller in AngularJS?
It's been asked before, and from the answers it doesn't look good. I'd like to ask with this sample code in consideration...
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Running multiple commands in one line in shell
Say I have a file /templates/apple and I want to
6 Answers
6
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Get the latest record from mongodb collection
...t record is fetched when your are limiting the output to just one document and it must be the top document in collection.
– kailash yogeshwar
Nov 23 '16 at 16:58
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Is inject the same thing as reduce in ruby?
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Yes, and it's also called fold in many other programming languages and in Mathematics. Ruby aliases a lot in order to be intuitive to programmers with different backgrounds. If you want to use #length on an Array, you can. If you ...
Visual Studio immediate window command for Clear All
Is there a command to clear the immediate window in Visual Studio?
7 Answers
7
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Why doesn't django's model.save() call full_clean()?
...matic" validation option which is both simple enough to actually be useful and robust enough to handle all the edge cases is -- if it's even possible -- far more than can be accomplished on the 1.2 timeframe. Hence, for now, Django doesn't have any such thing, and won't have it in 1.2. If you think ...