处理器无疑是计算机中最重要的部件,但并不是唯一的部件 。一台计算机也需要随机访 问存储器(R A M)来存放机器码指令以便让处理器执行。计算机还必须有一些方法使这些指 令进入R A M(输入设备)以及一些方法使程序执行结果得以看见(输出设备)。前面讲过, R A M是易失性的,当断电时,它的内容就会丢失。所以计算机中另一个有用的部件是永久存 储设备,当计算机断电的时候,它们可以保存代码和数据
INTRODUCTION Objectives Brightness CLeanliness OPurification-dissolving grade Historical background a Major concerns ◇ Costs◇ Environmental◇ Energy South China University of Technology
The only difference between a fat and an edible oil is that at ambient temperature a fat is semi-solid, and appears more or less firm to the touch, and an oil is liquid. They are both of similar general chemical composition. Edible oils are completely different in chemical form to mineral oils that are used as fuels or for lubrication. Most mineral oils are hazardous to human health and should not be even a small
The Function of a Scanner Reading characters from the source code and form them into logical units called tokens Tokens are logical entities defined as an enumerated type – Typedef enum {IF, THEN, ELSE, PLUS, MINUS, NUM, ID,…} TokenType;