A const problem

[compuKidd]

is there a power function that is concidered const? like a^2?

my problem is:

const int a=2;
char b[a];
double b[pow(2,a)];

this is not possible since pow is not const, now 2*a will work (if that is what you want) but power operation doesn't since there is no operator that is concidered constant by the compiler (I guess), is there a solution for this other than:

const int a=2;
const int b=4;
double a[b];

my real code is here:

template <int branchOutNum=2,int k=1,int n=3>	// note branchOutNum=2^k is a must
class viterbiState
{
	viterbiState *states[branchOutNum];

	char input[n];
	char estimate[k];

	viterbiState(){}
};

so I need both k and 2^k (banchOut) and it is a must that branchOut=2^k, so I just would need the user to enter them as so, otherwise I'm in trouble, and I think thats not good programming.

so any ideas to solve this one?

thanks