c++ - STL iterators: Prefix increment faster? -

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possible duplicates:
preincrement faster postincrement in c++ - true? if yes, why it?
is there performance difference between i++ , ++i in c++?

i got told when using stl , it's iterators, should use ++iter instead of iter++.

i quote:

because can faster, never slower

is true?

yes. true in general. postfix increment burdened task of preserving , returning old value of iterator. takes time , effort, makes slower.

it true overloaded increment/decrement operators implement traditional pre/post semantics.

this topic beaten death. search here on "prefix postfix" large number of more detailed explanations.


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