11,22,33,45,( ),71
A.53
B.55
C.57
D.59
参考答案:B
解析: 各项除以3的余数分别为2,1,0,0,1,2构成对称数列,故选B。
牙髓炎患牙的定位用()
A.X线检查
B.电活力测验
C.探诊
D.叩诊
E.温度试验
有以下程序: #include<iostream> using namespace std; class Base public: Base() x=0; int x; ; class Derived1:virtual public Base public: Derived1() x=10; ; class Derived2:virtual public Base public: Derived2() x=20; ; class Derived:public Derived1,protected Derived2 ; int main() Derived obj; cout<<obj.x<<endl; return 0; 该程序运行后的输出结果是______。