实现OPT、FIFO、LRU、Clock等页面替换算法。接收用户输入参数，包括程序长度（页面数）、页框个数及页面大小，输出结果采用不同颜色区分命中、替换及直接加入空闲块。-Implementation of OPT, FIFO, LRU, Clock and other page replacement algorithm. Receive user input parameters, including the length of the program (page number), page number and page size, the output results using different colors to distinguish between hit, replace and direct join free block.