分别用NumberFormat类的方法以及编写的类中的方法输出5的平方根。 通过一个20次的循环，每次获取1～8之间的一个随机数。-Methods were used and the preparation of the NumberFormat class methods in the class output of the square root of 5. 20 times through a loop, each time for between 1 to 8, a random n

QuickHit小游戏,主要是为初学者练习抽象类和对象以及练习循环和输入输出，随机数等的使用。-QuickHit game for beginners to practice abstract classes and objects, as well as practice cycle and input and output, the use of random number.