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） We won't hook up with the server for this app or website right now. There might be a lot of site visitors or a configuration mistake. Attempt once more later, or Make contact with the app or Web site owner. 查看 時間: https://pearlaquatics.my/4-facts-about-maintaining-your-aquarium-by-a-fish-tank-cleaner/