Euclidean norm on the Eisenstein integers
= Euclidean norm on the Eisenstein integers
{c}
Every complex number is within squared distance at most $3/4$ of an Eisenstein integer: write it as $x+y\omega$ and round $x$ and $y$ to integers. Therefore, for nonzero $\beta$ and arbitrary $\alpha$, a nearest lattice point $q$ to $\alpha/\beta$ gives
$$
N(\alpha-q\beta)<N(\beta).
$$
The norm makes the Eisenstein integers a <Euclidean domain>.