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SQL query to group by day
I want to list all sales, and group the sum by day.
8 Answers
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How to add directory to classpath in an application run profile in IntelliJ IDEA?
...order of the window or by pressing Alt + 1
find your project or sub-module and click on it to highlight it, then press F4, or right click and choose "Open Module Settings" (on IntelliJ 14 it became F12)
click on the dependencies tab
Click the "+" button on the right and select "Jars or directories.....
Write a program to find 100 largest numbers out of an array of 1 billion numbers
... number in the queue (the head of the queue), remove the head of the queue and add the new number to the queue.
EDIT:
as Dev noted, with a priority queue implemented with a heap, the complexity of insertion to queue is O(logN)
In the worst case you get billionlog2(100) which is better than billion...
How can I remove a flag in C?
There is a variable that holds some flags and I want to remove one of them. But I don't know how to remove it.
3 Answers
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Why does C# allow {} code blocks without a preceding statement?
...estrict the scope of some local variables. This is further elaborated here and here. Look at João Angelo’s answer and Chris Wallis’s answer for brief examples. I believe the same applies to some other languages with C-style syntax as well, not that they’d be relevant to this question though.
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HTML anchor link - href and onclick both?
I want to author an anchor tag that executes some JavaScript and then proceeds to go wherever the href was taking it. Invoking a function that executes my JavaScript and then sets window.location or top.location to the href location doesn't work for me.
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Is there a rule-of-thumb for how to divide a dataset into training and validation sets?
Is there a rule-of-thumb for how to best divide data into training and validation sets? Is an even 50/50 split advisable? Or are there clear advantages of having more training data relative to validation data (or vice versa)? Or is this choice pretty much application dependent?
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Accessing an array out of bounds gives no error, why?
...defined Behavior.
There is a lot that is not specified by the language standard, for a variety of reasons. This is one of them.
In general, whenever you encounter undefined behavior, anything might happen. The application may crash, it may freeze, it may eject your CD-ROM drive or make demons com...
Understanding exactly when a data.table is a reference to (vs a copy of) another data.table
I'm having a little trouble understanding the pass-by-reference properties of data.table . Some operations seem to 'break' the reference, and I'd like to understand exactly what's happening.
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REST vs JSON-RPC? [closed]
I'm trying to chose between REST and JSON-RPC for developing an API for a web application. How do they compare?
15 Answers
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