I came across with the code syntax
d //= 2
// is a floor division operator. The
= beside it means to operate on the variable "in-place". It's similar to the
*= operators, if you've seen those before, except for this is with division.
Suppose I have a variable called
d. I set it's value to
65, like this.
>>> d = 65
d //= 2 will divide
d by 2, and then assign that result to d. Since,
d // 2 is 32 (32.5, but with the decimal part taken off),
d becomes 32:
>>> d //= 2 >>> d 32
It's the same as calling
d = d // 2.