Activity

Objectives

1.

Learn about variables.

2.

Learn about assignments.

3.

Learn about input and output.

4.

Learn about numerical expressions.

5.

Learn about program neatness.

6.

Strengthen previous knowledge.

Resources

1.

Your class notes.

2.

The online help facilities of Windows and the C++ compiler.

Plan

1.

Create your programs, compile and execute them.

2.

Create the second modified program.

3.

Archive your second program on the Captain's Unix account.

4.

E-mail the programs to the TA greska@eng.fsu.edu.

5.

Define the vocabulary.

6.

Look at the critical thinking questions.

7.

Email in your answers (one per team) to the TA.

Critical Thinking Questions

1.

What output do you get from the statement:

    cout << "H" << "el" << 'l' << 'o' << endl;

2.

What output do you get from the statement:

    cout << "0.500 = " << 0.500 << endl;

3.

What is the difference in output between the program pieces on the left and on the right:

    cout << "Line 1$\backslash n$Line 2$\backslash n$";       cout << "Line 1$\backslash n$";
                                      cout << "Line 2$\backslash n$";

4.

What is the difference in output between the program pieces on the left and on the right:

    cout << "Line 1$\backslash n$";      cout << "Line 1" << endl
    cout << "Line 2$\backslash n$";           << "Line 2" << endl;

5.

What should you get from the statement:

    cout << "\a" << "Hi" << endl << "there" << endl;

(Does not work on the PCs, but works on Unix.)

6.

Why is the program on the right much better than the one on the left:

    #include <iostream.h>            #include <iostream.h>
    main ( ) {                main ( ) {
       int a;                           int a;
       ...                              int b;
       int b;                           ...
       ...                              ...
       a=1;                             a=1;                
       b=3;                             b=3;                
       cout << a+b << endl;             cout << a+b << endl;
       ...                              ...
    }                                }

(The dots stand for lots of other statements that are not important.)

7.

What is obviously wrong (except lack of neatness):

    #include <iostream.h>
    main ( ) {
    int pi;
    ...
    pi = 3.141593;
    ...
    return 0;
    }

8.

Why is the program on the left much better than the one on the right:

    #include <iostream.h>           #include <iostream.h>       
    main ( ) {               main ( ) {           
       float pi = 3.141593;            float pi;        
       ....                            ....                        
       ....                            pi=3.141593
       ....                            ....
       area = pi*r*r                   area = pi*r*r
       ....                            ....

(The dots stand for lots of other statements that are not important.) The size of the program (number of lines or number of characters) is not an important consideration.

9.

Why is the comment on the left much better than the one on the right:

    #include <iostream.h>           #include <iostream.h>       

    main ( ) {            	   	main ( ) {
       // Declarations:                // Declarations:

       // Define pi:                   float pi = 3.141593; // pi is defined
       float pi = 3.141593;            ....
       ....                            ....

(The dots stand for lots of other statements that are not important.) The size of the program (number of lines or number of characters) is not an important consideration.

10.

List at least four types of people that can benefit from the comments that you put in your program? Why?

(a)

(b)

(c)

(d)

11.

Can you store arbitrarily large integers in an int? In a long int?

12.

Can you store arbitrarily large floating point numbers in a float? In a double?

13.

Can you store arbitrarily accurate floating point numbers such as $\pi$ or $\sqrt 2$ in a float? In a double?

14.

What do you get from:

    cout << "3*3 = " << 3*3 << endl;

15.

What do you get from:

    float a; ...; a=1.5; cout << a << endl;

16.

What do you get from, and why:

    int a; ...; a=1.5; cout << a << endl;

17.

What do you get from, and why:

    cout << ".33 = " << 1/3 << endl;

18.

What do you get from, and why:

    cout << ".33 = " << 1./3 << endl;

19.

What do you get from, and why:

    cout << "Large: " << 300000*300000 << endl;

20.

What do you get from, and why:

    cout << "9 = " << 1+2*3 << endl;

21.

What do you get from, and why:

    cout << ".25 = " << 1./2.*2. << endl;

22.

What do you get from, and why:

    cout << "1 = " << 1./2./2. << endl;

23.

What do you get from:

    int i; ...; i=1; cout << i++; cout << i << endl;

24.

What do you get from:

    int i; ...; i=1; cout << ++i; cout << i << endl;

25.

Explain what happens during the execution of:

    int i,j; ...; cin >> i >> j;

Exercises

1.

How do you create a simple table?

2.

Print out a zero (O) if a number is odd and a 3 (an inverted E) if the number is even, using only what you have learned so far.

Evaluation

1.

Give two strengths of your group.

2.

Indicate two areas for improvement.

3.

What two new insights did your group obtain?

4.

Give two strengths of the class so far.

5.

Indicate two areas for improvement of the class.

6.

What two new insights did you obtain about the class?