编程序实现下述磁盘调度算法,并求出每种算法的平均寻道长度：

要求设计主界面以灵活选择某算法，且以下算法都要实现

1、先来先服务算法（FCFS）

2、最短寻道时间优先算法（SSTF）

3、扫描算法（SCAN）

4、循环扫描算法（CSCAN）

-Programmed to achieve the following disk scheduling algorithms, and calculate the average seek length of each algorithm: to design the main interface with the flexibility to choose an algorithm, and must achieve the following algorithm 1, first come first served algorithm (FCFS) 2, the shortest seek time first algorithm (SSTF) 3, scan algorithm (SCAN) 4, cyclic scan algorithm (CSCAN)