There are some syntax errors:
int myPay, yourPay; // OK long good-by ; // bad identifier: "-" not allowed short shrift = 0; // OK double bubble = 0, toil= 9, trouble = 8 // missing ";" at end. byte the bullet ; // bad identifier: can't contain a space int double; // bad identifier: double is a reserved word char thisMustBeTooLong ; // OK in syntax, but a poor choice // for a variable name int 8ball; // bad identifier: can't start with a digit float a=12.3; b=67.5; c= -45.44; // bad syntax: don't use ";" to separate variables
public class Example
{
public static void main ( String[] args )
{
long hoursWorked = 40;
double payRate = 10.0, taxRate = 0.10;
System.out.println("Hours Worked: " + hoursWorked );
System.out.println("pay Amount : " + (hoursWorked * payRate) );
System.out.println("tax Amount : " + (hoursWorked * payRate * taxRate) );
}
}
The example program, contains three variable declarations. The variables are given initial values.
The character * means multiply.
In the program,
(hoursWorked * payRate)
means to
multiply the number stored in hoursWorked
by the number stored in payRate.
Important Idea: When used as part of an expression, the name of a variable represents the value it holds.
(An expression is a part of a statement that asks for a value to be calculated.)
When it follows a character string,
+ means to
add characters to the end of the character string. So
"Hours Worked: " + hoursWorked
makes a
character string starting with "Hours Worked: " and ending with
characters for the value of hoursWorked.
The program prints:
Hours Worked: 40 pay Amount : 400.0 tax Amount : 40.0
To run this program, copy it from your Web browser, paste it into Notepad or other text editor, save it to a file, compile, and run it. Or use one of the web pages mentioned two pages earlier.
It really helps to see programs running. This tricks you brain into thinking that it did something clever, and should remember what happened.
Why did the program print the first 40 without a decimal point,
but printed the
second one with a decimal point as 40.0 ?
(Hint: look at the variable declarations.)