Re: Why is VC++ STL so slow?

Hello,
Could you write the simplest example when problem accure?

If problem accure only in map and set container I think that is
connected with container implementation.
Microsoft prefer implementation map with as hash_map (MFC CMap it is
hash_map). Generally hash_map is faster then normal map (finding time,
acces time etc.). But adding element to hash_map is slower. (It is
connected with hashing algorithm if you add many elements hashing
algorithm is called many times). Therefore, If you add alements to
hash_map first you should initialize size of hash_map. Initialization
is very important for hash_map.

Generally If you know size of container you should initialize size
before adding element. :)

UINT iSize = 1000000;
myMap.initialize(iSize);//very important for hash_map

for(int idx=0; idx<iSize; idx++)
{
  addElementToMap(myMap,idx);
}

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