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Effectively deleting elements of a map.

1
Hello,

I use a map and after I stored and used elements I would like to erase the map.

The map I use is defined like that :
Expand|Select|Wrap|Line Numbers
  1. map<MyClass *, long long, myClassCmp>
  2.  
and MyClass simply contains two int

Then I use the clear function:
Expand|Select|Wrap|Line Numbers
  1. myMap.clear()
Nevertheless it seems that the memory isn't free. How to be sure to free the memory ?

Many thanks

JS
Aug 28 '07 #1
1 1116
weaknessforcats
9,208 Expert Mod 8TB
map, like most STL containers may not release memory after a clear(). Memory is expensive to allocate and one it is allocated the container may have to be prodded to release it.

Create an empty map and swap it with your cleared map using the map's
swap() method.
Aug 28 '07 #2

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