ATL / WTL / STL

class Class {
    OtherClass* pObj;
public:
    Class() { pObj = new OtherClass(); }
    ~Class() { delete pObj; }
};

...

Class* arr = new Class[10];
...
delete arr; // The memory chunk pointed to by arr is freed, but
            // the destructor is only called for the first object.
            // Hence you'll have 9 memory leaks (see ~Class())
            // delete [] ensures that all destructors for all elements
            // are called.

struct STLDeleteObject
{
	template<typename T>
	void operator()(const T* ptr) const
	{
		delete ptr;
	}
};

std::for_each(c.begin(), c.end(), STLDeleteObject())

struct STLDeleteArray
{
	template<typename T>
	void operator()(const T* ptr) const
	{
		delete[] ptr;
	}
};

std::for_each(c.begin(), c.end(), STLDeleteArray())