页面置换算法理解页面置换算法,实现先进先出（FIFO）置换算法和最久未使用（LRU）置换算法。给出任意的输入流，计算置换次数。-Page replacement algorithms understand page replacement algorithm, first in first out (FIFO) replacement algorithm and least-recently used (LRU) replacement algorithm. Any given input stream, calculate the number of replacement.