再用n2的时间（两重循环）枚举d-c，并将b-c的值作为键，在Hash数组中查找是否存在。如果能找到vital相同的node点，则找到了一组满足 d-c = a+b的值。（注意检查a b c d 四个数不重复） Live crops are more than just decorative factors within a freshwater aquarium. They contribute to oxygenation, assist preserve water quality, and supply pure habitats for fish. 三個月 返 回 兩天 From preserving pris... https://pearlaquatics.my/author/sushant/page/6/