Implement first into and then out of the stack fea
5.0
A stack is a memory that performs a "first in, then out" algorithm. The data is stored in the (push) storage area one by one. There is an address pointer that always points to the data unit where the last data is pushed into the stack. The register where the address pointer is stored is called the stack indicator. The first unit of data is called "bottom of stack", and the last unit of data is called "top of stack". Data is stored one by one. This process is called "stack pressing". In the process of stack pressing, every data that is pressed into the stack is placed in the following unit connected with the previous unit, and the address in the stack indicator is automatically increased by 1. When reading these data, the data is read according to the address in the stack indicator, and the address number of the stack indicator is automatically reduced by 1. This process is called "pop pop". In this way, the principle of "first in, then out" can be realized.