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#include<iostream>#include<cmath>using namespace std;class A	{
   		public:		    A(int xx=0,int yy=0){
   x=xx;y=yy;cout<<"A_init1"<<endl;}		    A(A &a){
   x=a.x;y=a.y;cout<<"A_init2"<<endl;}			int getx(){
   return x;}			int gety(){
   return y;}		private:		    int x;			int y;	}; class B	{
   		public:			B(int x1,int x2,int x3,int x4,int length):p1(x1,x2),p2(x3,x4)			{
   				len=length;				cout<<"B_init1"<<endl; 			}			B(A xp1,A xp2);			B(B &l);			double getlen(){
   cout<<len<<endl;return len;}		private:			A p1;			A p2;			double len;	}; 	B::B(A xp1,A xp2):p1(xp1),p2(xp2)			{
   				double x=static_cast<double>(p1.getx()-p2.getx());				double y=static_cast<double>(p1.gety()-p2.gety());				len=sqrt(x*x+y*y);				cout<<"B_init2"<<endl; 			}	B::B(B &l):p1(l.p1),p2(l.p2){
   len=l.len;cout<<"B_init3"<<endl; }	int main()	{
   	A m(0,0);	A n(0,0);	B p(m,n);	cout<<endl;	B q(p);	cout<<endl;	B c(2,3,4,5,10);	return 0;	}