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important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 emblems are either the residence of Central Garden & Pet Organization, its subsidiaries, divisions, affiliated and/or associated firms or maybe the assets of their respective entrepreneurs. गड़बड़ियां ठीक की... https://pearlaquatics.my/how-to-keep-your-aquarium-malaysia/