By any chance, do you happen to have natural merge in Python?

I had to replace "undefined" by a forward slash in the WordPress backend, then it worked. When I enter a forward slash in the comment field, it also comes out as "undefined". Very strange.

Ok, now I now why you always wrote "undefined". It happens to mee, too ;-)

Hi Arif,

thanks for your comment. Do you refer to

n*1, n/2 * 2, n/4 * 4, etc... ?

Imagine you have 16 elements.
In the first step, you have to merge 16 times 1 element = 16 steps
In the second step. you now have 8 blocks of 2 elements to merge, 8 * 2 = 16 / 2 * 2 = 16 steps
In the third step, you then have 4 blocks of 4 elements, 4 * 4 = 16 / 4 * 4 = 16 steps
In the fifth step, you have 2 blocks of 8 elements, 2 * 8 = 16 / 8 * 8 = 16 steps

If you replace 16 by n, you get n*1, n/2*2, n/4*4, n/8*8, or just always n.