[Aardwolf]

Think about all tricks you can so in decimal, but in base 2 instead.

E.g in decimal you can multiply by ten by appending a zero, so in binary you multiply by 2 by doing so. And left shifting by 1 is what appends a zero.

Or you can take approximate log base ten in decimal by counting amount of digits, so in binary you can approximate log2 this way (counting up to most significant one-bit). Etc...