Hi,
I need use map faster as possible (I store in the map data about open
network connections).
First a question, this code fragment is from "The C++ Programming.... ....
3rd edition by B. Stroustrup"
m[k] is equivalent to (*(m.insert(mak e_pair(k,V()))) .first)).second
The work of V() is to create a void base tape? if so, the expression:
m.insert(make_p air(k,objItem))
where objItem is my object is a better choice?
thanks
Marco C. 3 1437
mcassiani wrote: I need use map faster as possible (I store in the map data about open network connections).
First a question, this code fragment is from "The C++ Programming.... .... 3rd edition by B. Stroustrup"
m[k] is equivalent to (*(m.insert(mak e_pair(k,V()))) .first)).second
The work of V() is to create a void base tape? if so, the expression:
Right.
m.insert(make_p air(k,objItem))
where objItem is my object is a better choice?
Could be. You won't know until you actually put it into the working
program and run it under a profiler. Speculation costs very little and
has no real value. Get results from timing your process, then judge.
V
mcassiani wrote: Hi,
I need use map faster as possible (I store in the map data about open network connections).
These days, memory tends to be a lot faster than I/O. Usually, the
overhead of map will be insignificant. Just make sure the objects in
the map don't perform too much I/O - i.e. cheap default ctors.
HTH,
Michiel Salters This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics |
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