#define BIG_NUMBER (3.4e+38f)

struct Math
{
	static float Abs(float F)
	{
		return F > 0.0f ? F : -F;
	}

	static float Sqrt(float F)
	{
		int NUM_REAPEAT = 16;
		int k;
		float t;
		float buf = F;

		for (k = 0, t = buf; k < NUM_REAPEAT; k++)
		{
			if (t < 1.f)
				break;
			t = (t * t + buf) / (2.f * t);
		}

		return t;
	}

	static float InvSqrt(float F)
	{
		float FHalf = 0.5f * F;
		int i = *(int*)&F;
		i = 0x5f3759df - (i >> 1);
		F = *(float*)&i;
		F = F * (1.5f - (FHalf * F * F));

		return F;
	}
};