We are given integer $w$, with $\betw{w}{100}$. All we want to know if whether it is possible to divide $w$ into two parts, such that $\forall x \in \set{a, b}, x \mod 2 \equiv 0 \land x \in \mathbb{Z}^+$. This is quite a simple problem, the only case you might overlook is when $w = 2$; the two parts do not need to be equal, however they must both be positive.