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) Live crops tend to be more than simply ornamental aspects in the freshwater aquarium. They lead to oxygenation, aid keep drinking water top quality, and provide all-natural habitats for fish. ● पोस्ट, स्टोरीज़, ... https://pearlaquatics.my/free-consultation/