- Increases the value of a variable by one

Variable++; or ++Variable;

num++; is equivalent to num=num+1; (if num=20, then num++; will result in num=21)

- Both statements behave in the same way when they are used to increment a variable in a separate statement

- If we use them in the middle of a larger expression (e.g., alpha=num++ * 3) they can yield different results

- Decreases the value of a variable by one

Variable--; or --Variable;

num--; is equivalent to num=num-1; (if num=20, then num--; will result in num=19)

- Both statements behave in the same way when they are used to increment a variable in a separate statement

- If we use them in the middle of a larger expression (e.g., alpha=num-- * 3f1 they can yield different results

- It instructs the computer to print a message or the value of an expression on the screen

cout << ExprOrString ... ;

- As the syntax template shows, the insertion operator (<<) can appear several times in a single cout1

- Example

cout << "The sum is " << sum;

or equivalently

cout << "The sum is ";
cout << sum;

- Strings must always be enclosed in double quotes (" ")

- More examples

<Table from page 69)>

- To instruct the computer to print something on a separate line, we must use the dentifier endl (i.e., end of line)

- Examples

cout << "Hi";
cout << "there";

will print:
Hithere

cout << "Hi" << endl;
cout << "there";

will print:
Hi
there

Debugging your program

<Figure 2-6, page 80)

Recommended exercises

- All Quick Check excersices (pages 85,86)

- Excersices 3 (page 88), 5, 6, 10 (page 89), 11 (page 90)