下面程序的运行结果是【 】。 include <iostream> using namespace std; class count { static int n; public: count() { n++; } static int test() { for(int i=0;i<4;i++) n++; return n; } }; int count::n = O; int main() { cout<<count:: test()<<' '; count c1, c2; cout<<count:: test()<<endl; return 0; }