下列程序的输出结果是( )。 #include<iostream> using namespace std; class TestClass{ static int i; public: TestClass(){i++;} ~TestClass(){i--;} static int getVal(){return i;} }; int TestClass::i=O; void fun(){TestClass ob2;cout<<ob2.getVal();} int main(){ TestClass ob1; fun(); TestClass*ob3=new TestClass;cout<<ob3->getVal(); delete ob3;cout<<TestClass::getVal(); return 0; }