Bing Xi Computer Technology and Society 270378-2349 Assignment 9

1. 
   Chapter 6, page 320, 1. What does it mean to say that a programming language is a machine independent?
   

2. 
   Chapter 6 on page 320, 7. Suppose the function f expects two numeric values as its inputs and returns the smaller of the two values as its output value. If w, x, y, and z represent numeric values, what is the result returned by f(f(w,x), f(y,z)?
   

3. 
   Draw the parse tree for the expression x - y * z + y * x based on the syntax diagrams in Figure 6.16 on page 299.
   

4. Download Python 2.5 and read the introduction to the IDLE programming environment that comes with Python 2.5.

1) Enter the following Python program (note that spaces at the beginning of the line make a difference in Python):

temp = input("What is the temperature?")

if temp < 5:

print "It is rather cold."

else:

print "This is fine."

2) Change the program such that it checks if the temperature is higher than 30 and if so then prints out appropriate message.

temp = input("What is the temperature? ")

if temp < 5:

print "It is rather cold."

elif temp > 30:

print "It is ridiculously hot."

else:

5. 
   Chapter 6, 325, social issue 4. To what extent is a programmer who helps develop a violent computer game responsible for any consequences of that game? Should children’s access to computer games be restricted? If so, how and by whom? What about other groups in society, such as convicted criminals?
   

Children’s access to benign computer games is reasonable, but their access to malign or violent games should be strictly restricted. Because children tend to learn what they see around them, they might very much try to do the things they do in the games. The restrictions should not only come from schools, parents, but also from the government or the legislature. Only by establishing rules or even laws the restrictions can truly be regarded.