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） Standard screening and adjustment of salinity stages are important for that very well-remaining within your maritime lifetime. Generally utilize a trusted hydrometer or refractometer to evaluate salinity precisely... https://pearlaquatics.my/how-to-maintain-discus-fish/