有如下程序:#include using namespace std;class Part{public: Part(int x=0):val(x){cout<<val;} Part(){cout<<val;)private:int val;);class Whole{ public: Whole(int X,int Y,int z=0):p2(x),pl(y),val(z){cout<<-val;}Whole(){cout<<val;} private:Part pl,p2; int val;};int main(){Whole obj(1,2,3);return 0;} 程序的输出结果是
A.123321
B.213312
C.213
D.123123