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essential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） All trademarks are both the house of Central Back garden & Pet Business, its subsidiaries, divisions, affiliated and/or connected firms or maybe the assets in their respective entrepreneurs. 三個月 返 回 一周 ● ... https://pearlaquatics.my/reasons-to-maintain-your-aquarium/