@Prestidigitor
@NoContextHumans
50% true.
"姦しい"(kashimashii) means carping/noisy.
But, "強姦"(goukan) means rape.
Going back to the original meaning, it means "a man and woman passing each other in defiance of rules and ethics" or "unrighteousness between the sexes".
@ElectroBOOMGuy
@engineers_feed
yes, The right-hand method works only if
{(10^n)±a}×{(10^m)±b} a, b, m, n∈ℕ∧a, b<10
Of course, the calculation is possible even if a and b are large, but the advantage of the method is lost.