1 Let $w=-\frac{1}{2}+\frac{\sqrt{3}}{2} \cdot i\left(i^{2}=-1\right)$, then the number of different values that the algebraic expression $w^{m}+w^{n}+w^{l}(m, n, l$ are pairwise distinct integers) can take is $\qquad$ .
1 10. $\omega=\cos \frac{2 \pi}{3}+i \cdot \sin \frac{2 \pi}{3}$, so $\omega^{3 k}=1, \omega^{3 k-1}=\omega, \omega^{3 k+2}=\omega^{2}=$ $-\left(\cos \frac{\pi}{3}+i \cdot \sin \frac{\pi}{3}\right)$. From this, we know that $\omega^{m}+\omega^{n}+\omega^{l}(m, n, l$ are distinct integers) can take the values $3, 3 \omega, 3 \omega^{2}, 2+\omega, 2+\omega^{2}, 1+\omega+\omega^{2}=0, 1+2 \omega, 1+2 \omega^{2}$, $2 \omega+\omega^{2}, \omega+2 \omega^{2}$, for a total of 10 different values.