实现了操作系统的内存模拟管理功能，简单易懂，适合学习。此文档实现了内存管理的动态分区分配，固定分区分配，显示内存分配情况，可实现回收再利用功能。-Achieved the operating system memory management functions simulated, simple and easy to understand, suitable for learning. This document implements the dynamic memory management