Question

I need to set an int variable in each iteration +-1, the range should be between 0-10. When i add 1 to 10 -> 0 when i add -1 to 0 -> 10. I know i need to go with modulo here but cannot find any solution.

Answer 1

This seems to easy, but if you really want to use modulo, did you try;

    x = (x + y) % 11;
    if (x < 0) x += 11;

or for “ultimate readability” and probably still better performance just

    x = x + y;
    if (x < 0)  x += 11;
    if (x > 11) x -= 11;

Please note that the requirements locks y down to being -1 or 1.