计算：(n/r(K/C0I's.{9a.q
19+299+3999+49999(n/r(K/C0I's.{9a.q
算式：提示1t8A:x8L.Z4a6r.`*i:k-C.b(n/r(K/C0I's.{9a.q
=-x5s2Q;J0|7x;@.U3h9|:@(n/r(K/C0I's.{9a.q