STL set / multiset size

The size of set / multiset
set.size (); // Return the number of elements in the container
set.empty (); // To determine whether the container is empty
Note: They do not have a resize method

    set<int> setIntA;
	setIntA.insert(3);
	setIntA.insert(1);
	setIntA.insert(7);
	setIntA.insert(5);
	setIntA.insert(9);

	if (!setIntA.empty())
	{
		int iSize = setIntA.size();		//5
	}

max_size () can save the maximum number of elements
Example:

#include <set>
#include <iostream>
#include <functional>
#include <algorithm>

using namespace std;

int main()
{
	set<int> setInt;
	cout<<"max_size: "<<setInt.max_size()<<endl; //能保存的最大的元素个数

	for(int i = 0; i < 10; i++)
	{
		setInt.insert(i);
	}
	cout<<"after inserting 10 elements max_size: "<<setInt.max_size()<<endl; //能保存的最大的元素个数

	system("pause");
	return 0;
}

Compilation environment: vc ++ 2010 learning version
Operation result: