c++ - What's the most efficient way to erase duplicates and sort a vector? -

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I probably have to take a C ++ vector with lots of elements, remove duplicates, and sort it.

I currently have the code below, but it does not work. 

  vec.erase (std :: unique (vec.begin (), vec.end ()), vec end ()); Std :: sort (vec.begin (), vec.end ());

How can I do this correctly?

Additionally, erasing the first duplicate (like the one coded above) or what is faster to sort first? If I sort the first, what is std :: unique executed?

Or there is another (perhaps more efficient) way to do this. ?

I agree and; A good idea can be here even if you are trapped using vectors, if you have enough duplicates, then you might be better to create a set to do dirty work.

Let's compare the three ways:

Sort by vector, exclusive 

  (vec. Start (), vec.end ()); Vec.erase (unique (vec.begin (), vec.end ()), vec.end ());

Convert (manual) 

  set to set

Convert to set up (using constructor) 

  set & lt; Int & gt; S (vec.begin (), vec.end ()); Vec.assign (s.begin (), S. & ());

How do these work as a number of duplicates:

Summary : When the number of duplicates is large enough, convert it to a set to actually And then dump data back into a vector

and for some reason, the fixed conversion is progressing faster than the set constructor - At least the toy used by me on random data.


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