18. Given that $a, b, c$ are non-zero rational numbers, and satisfy $a b^{2}=\frac{c}{a}-b$, then $\left(\frac{a^{2} b^{2}}{c^{2}}-\frac{2}{c}+\frac{1}{a^{2} b^{2}}+\frac{2 a b}{c^{2}}-\frac{2}{a b c}\right) \div\left(\frac{2}{a b}-\frac{2 a b}{c}\right) \div \frac{101}{c}=$ $\qquad$
Answer: $-\frac{1}{202}$