以下程序运行后的输出结果是 【10】 #include <iostream> #include <string> using namespace std; class Y; class X {int x;char *strx; public:x(int a,char *str) { x=a; strx=new char[strlen(str)+1]; strcpy(strx,str); }void show(Y &oB) ; }; class Y { private:int y;char *stry; public:Y(int b,char *str){ y=b; stry=new char[strlen(str)+1]; strcpy(stry, str); } friend void X::show(Y &oB) ; }; void X::show(Y &oB) { cout<<strx<<","; cout<<ob.stry<<end1; } int main() { X a(10,"stringX"); Y b(20,"stringY"); a.show(B) ; return 0; }