operator new【STL】

    知识点：    C++中的::operator new和::operator delete只负责分配空间，不负责构造与析构，与malloc和free功能差不多。

    测试：

    

 #include <iostream>using namespace std;class A{public:A(){cout<<"default construction"<<endl;}A(int t_){cout<<"int construction"<<endl;}~A(){cout<<"destruction"<<endl;}public :int t;};int main(){cout<<"111"<<endl;A *ap = (A*)(::operator new( (1*sizeof(A) )));//ap->A(2);cout<<"222"<<endl;//destroy(ap);::operator delete(ap);cout<<"333"<<endl;return 0;}