Simplify Algorithm

Question

Hello,
I am trying to develop an algoithm to store all the top left hand co-ordinates of each square on a snakes and ladders board like so.
The first line goes from left to right then up one then right to left etc.. like so.
22 23 24 etc....
21................................. 12 11
0 1 2 3 4 5 6 7 8 9 10
The algorithm that i have come up with to store the x coord of each square is.
660 * (i/12%2)) + (i/12%2 * -2 + 1) * i%12 * 60
i represents the number of each square from 0 to 71.
How can I simplify this algorithm to get rid of the duplicate sums,
e.g. i/12%2
Thanks
Andrew

Answer 1

How can I simplify this algorithm to get rid of the
duplicate sums,
e.g. i/12%2use mulitple lines and intermediate values
int foo = i/12%2;
660*foo + (foo-1)*i%12*60
but even better is to not use math to implement conditionals, and to document your magic numbers, for example:
int colCount = 12;
int rowNum = i/colCount;
int colNum = i%colCount; // assumes numbers run left to right..
// but odd rows run backwards
if((rowNum & 1) == 1) colNum = colCount - colNum -1;
then you can convert numbers into screen coordinates
xValue = xMargin + colNum*cellWidth;
one step at a time is better than a bunch o' math all stuffed onto one line.