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crucial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 can't connect to the server for this application or Web site presently. There may be an excessive amount of traffic or simply a configuration error. Attempt again later on, or Make contact with the application ... https://pearlaquatics.my/how-does-an-aquarist-maintain-their-aquarium-tank-fish-pond/