CODE:

#include 
#include 
#include 
using namespace std;

class Error : public runtime_error{
public:
	Error( const char* const Mes ) throw() : runtime_error( Mes ){}
};

class A{
public:
	A(){ cout << "コンストラクタA" << endl; }
	~A(){ cout << "デストラクタ~A" << endl; }
};

class B{
public:
	B(){ cout << "コンストラクタB" << endl; throw Error( "例外" ); }
	~B(){ cout << "デストラクタ~B" << endl; }
};

int main(){
	A* a = nullptr;
	B* b = nullptr;

	try{
		a = new A;
		b = new B;
	}
	catch( const exception& e ){
		cout << e.what() << endl;
	}

	delete a; a = nullptr;
	delete b; b = nullptr;

	return 0;
}

CODE:

class A{
public:
	A(){
		try{
			b=newB;
			c=newC;
			d=newD;
			e=newE;
			f=newF;
			g=newG;
			h=newH;
		}
		catch(...){
			delete h;
			delete g;
			delete f;
			delete e;
			//delete d;忘れた!!
			delete c;
			delete b;
		}
	}
	A~(){
		delete h;
		delete g;
		delete f;
		delete e;
		delete d;
		delete c;
		delete b;
	}
};