In C++, I can statically initialize an array, e.g.:
int a[] = { 1, 2, 3 };
Is there an easy way to initialize a dynamically-allocated array
No, you cannot initialize a dynamically created array in the same way.
Most of the time you'll find yourself using dynamic allocation in situations where static initialization doesn't really make sense anyway. Such as when you have arrays containing thousands of items. So this isn't usually a big deal.