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How to get all subsets of a set? (powerset)
..., ('a', 'c', 'd'), ('b', 'c', 'd'), ('a', 'b', 'c', 'd')]
If you don't like that empty tuple at the beginning, you can just change the range statement to range(1, len(s)+1) to avoid a 0-length combination.
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Why do == comparisons with Integer.valueOf(String) give different results for 127 and 128?
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There's a striking difference here.
valueOf is returning an Integer object, which may have its values cached between -128 and 127. This is why the first value returns true - it's cached - and the second value returns false - 128 isn't a ...
Do while loop in SQL Server 2008
...S SQL Server 2008 but you can change your WHILE loop logic, so as to USE like DO-WHILE loop.
Examples are taken from here: http://blog.sqlauthority.com/2007/10/24/sql-server-simple-example-of-while-loop-with-continue-and-break-keywords/
Example of WHILE Loop
DECLARE @intFlag INT
SET @intFla...
What's the advantage of a Java enum versus a class with public static final fields?
I am very familiar with C# but starting to work more in Java. I expected to learn that enums in Java were basically equivalent to those in C# but apparently this is not the case. Initially I was excited to learn that Java enums could contain multiple pieces of data which seems very advantageous ( ht...
Simple explanation of MapReduce?
... for Map and Reduce.
Map is a function which "transforms" items in some kind of list to another kind of item and put them back in the same kind of list.
suppose I have a list of numbers: [1,2,3] and I want to double every number, in this case, the function to "double every number" is function x ...
How do you connect to multiple MySQL databases on a single webpage?
...ro.mysql.php), use mysqli_xx functions or see the answer below from @Troelskn
You can make multiple calls to mysql_connect(), but if the parameters are the same you need to pass true for the '$new_link' (fourth) parameter, otherwise the same connection is reused. For example:
$dbh1 = mysql_conne...
How may I reference the script tag that loaded the currently-executing script?
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Simple and explicit. Reliable.
Don't need to modify the script tag
Works with asynchronous scripts (defer & async)
Works with scripts inserted dynamically
Problems
Will not work in older browsers and IE.
Does not work with modules <script type="module">
2. Select script by id
G...
How do I suspend painting for a control and its children?
I have a control which I have to make large modifications to. I'd like to completely prevent it from redrawing while I do that - SuspendLayout and ResumeLayout aren't enough. How do I suspend painting for a control and its children?
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Making text background transparent but not text itself
So I am having a problem. I have looked around and looked around but no luck. I would like to make the background of my body transparent but leave the text non transparent. As it is right now I keep making both the same opacity. Here is my code:
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How to create NS_OPTIONS-style bitmask enumerations in Swift?
...entation about interacting with C APIs, they describe the way NS_ENUM -marked C-style enumerations are imported as Swift enumerations. This makes sense, and since enumerations in Swift are readily provided as the enum value type it's easy to see how to create our own.
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