create lookup table instead of formulas about fivestage444 HOT 2 CLOSED

Thanks for the tip ! Packing 5 values in one byte was on my todo list, but the formulas are a bit more complicated.

from fivestage444.

ah...I mean use look-up table instead of formulas...
it can be initialized like:

private static byte[] GetPacked = new byte[243_8];
for (int i=0; i<243; i++) {
for (int j=0; j<5; j++) {
int l = i;
for (int k=1; k<=j; k++)
l /= 3;
GetPacked[i_8+j] = (byte)(l % 3);
}
}

and when I want to get the secnod value of byte i (i=0..242), just access GetPacked[i<<3|1]; or the third value:GetPacked[i<<3|2], etc.
of course it's faster than any formula.

from fivestage444.