Jason Hise wrote:
I was just playing around, trying to compute a square root at compile time. I came up with the following:
<code snip>
This works for most values, but unfortunately some ( like 80 ) end up oscillating and X never becomes equal to X2. How could I go about correcting this?
you can do something like this: template < unsigned int N, unsigned int X = 1, unsigned int X1 = 0, unsigned int X2 = ( X + N / X ) / 2 > struct Sqrt { enum { Value = Sqrt < N, X2, X > :: Value }; }; template < unsigned int N, unsigned int X, unsigned int X1 > struct Sqrt < N, X, X1, X1 > { enum { Value = X1 }; }; this code takes one more iteration to solve, but avoid the oscillation problem, I was not sure why you are using this ValueHolder struct so I took the liberty to remove it, but if you need it, you can bring it back without any problem.
-Jason Sérgio