堆栈实现。堆栈就是这样一种数据结构。它是在内存中开辟一个存储区域，数据一个 顺序地存入（也就是“压入——push”）这个区域之中。有一个地址指针总指向最后一个压入堆栈的数据所在的数据单元，存放这个地址指针的寄存器就叫做堆栈指示器。开始放入数据的单元叫做“栈底”。数据一个一个地存入，这个过程叫做“压栈”。在压栈的过程中，每有一个数据压入堆栈，就放在和前一个单元相连的后面一个单元中，堆栈指示器中的地址自动加1。读取这些数据时，按照堆栈指示器中的地址读取数据，堆栈指示器中的地址数自动减 1。这个过程叫做“弹出pop”。如此就实现了后进先出的原则。-Stack implementation. Stack is such a data structure. It was opened in memory a storage area, the data one by one sequentially deposited (ie " push- push" ) into this area. There is an address pointer always points to the last one where the data is pushed onto the stack data unit, the address pointer stored is called the stack pointer register. Start the data into a unit called the " bottom of the stack."　Data stored in one by one, this process is called " push."　In the push process, each having a data onto the stack, and the previous one is placed behind the unit is connected to a unit, the stack pointer in the address is automatically incremented by 1. Read the data, in accordance with the address of the stack pointer in the read data, the number of addresses in the stack pointer is decremented by one. This process is called " pop pop" . So to achieve a LIFO principle.