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What's the most efficient way to erase duplicates and sort a vector?
...to take a C++ vector with potentially a lot of elements, erase duplicates, and sort it.
23 Answers
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Why check both isset() and !empty()
Is there a difference between isset and !empty . If I do this double boolean check, is it correct this way or redundant? and is there a shorter way to do the same thing?
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querySelector and querySelectorAll vs getElementsByClassName and getElementById in JavaScript
... would like to know what exactly is the difference between querySelector and querySelectorAll against getElementsByClassName and getElementById ?
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Why use apparently meaningless do-while and if-else statements in macros?
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The do ... while and if ... else are there to make it so that a
semicolon after your macro always means the same thing. Let's say you
had something like your second macro.
#define BAR(X) f(x); g(x)
Now if you were to use BAR(X); in an if ...
Return type of '?:' (ternary conditional operator)
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Expressions don't have return types, they have a type and - as it's known in the latest C++ standard - a value category.
A conditional expression can be an lvalue or an rvalue. This is its value category. (This is somewhat of a simplification, in C++11 we have lvalues, xvalues a...
Date ticks and rotation in matplotlib
...sn't do anything, plt.gca() does not give you the axes you want to modify, and so plt.xticks, which acts on the current axes, is not going to work.
For an object-oriented approach not using plt.xticks, you can use
plt.setp( axs[1].xaxis.get_majorticklabels(), rotation=70 )
after the two avail_pl...
Get image data url in JavaScript?
... the same domain as the page, or has the crossOrigin="anonymous" attribute and the server supports CORS. It's also not going to give you the original file, but a re-encoded version. If you need the result to be identical to the original, see Kaiido's answer.
You will need to create a canvas eleme...
Convert System.Drawing.Color to RGB and Hex Value
... to develop the following two. The way I am doing it may have some problem and need your kind advice. In addition, I dont know whether there is any existing method to do the same.
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How to implement one-to-one, one-to-many and many-to-many relationships while designing tables?
Can anyone explain how to implement one-to-one, one-to-many and many-to-many relationships while designing tables with some examples?
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How do CUDA blocks/warps/threads map onto CUDA cores?
...ns.
The programmer divides work into threads, threads into thread blocks, and thread blocks into grids. The compute work distributor allocates thread blocks to Streaming Multiprocessors (SMs). Once a thread block is distributed to a SM the resources for the thread block are allocated (warps and sha...