因为$b_i$不一定是质数，所以应该用欧拉定理$ans = \sum_{i = 1}^{n}(a_i \times m_i^{\varphi(b_i) - 1} \times m_i)$,其中$m_i = \frac{\prod_{i = 1}^{n}b_i}{b_i}$