Question

How would you iterate over the following series in Javascript/jQuery:

1, -2, 3, -4, 5, -6, 7, -8, ...

Here is how I do this:

n = 1
while (...) {
  n = ((n % 2 == 0) ? 1 : -1) * (Math.abs(n) + 1);
}

Is there a simpler method ?

Answer 1

You could keep two variables:

for (var n = 1, s = 1; ...; ++n, s = -s)
  alert(n * s);