圆盘找数问题。设有以下20个随机数组成一个圆（首尾相接），分别求出连续的四个数之和为最大的四位数及其和值）以及连续的四个数之和为最小的四位数（输出整个数列、最大、最小的四个数及其和值。

要求：

1）. 圆盘类class circle中包含私有成员int num[20], int Max[4] , int Min[4],int sum_max, int sum_min, 同时根据需要增加私有或公有成员及必要的公有成员函数。

2）. 在程序中产生20个随机数.-Disc to find the problem. Has 20 random numbers to form a circle (end to end), respectively, obtaining four consecutive number and the largest of the four-digit and value) as well as four consecutive numbers and a minimum of four number (output of the entire series, maximum, minimum number of four and values. requirements: 1) the Disc class circle contains private member int num [20], int Max [4], int Min [4], int sum_max, int sum_min, at the same time according to the need to increase the private or public members and public member functions. 2) The random number generated in the program 20.