课后作业3----加减乘除（）

//An addition program

import javax.swing.JOptionPane; // import class JOptionPane

public class Addition2 {
public static void main( String args[] )
{
String firstNumber, // first string entered by user
secondNumber; // second string entered by user
int number1, // first number to add
number2, // second number to add
sum,cha,ji,shang; // sum of number1 and number2

// read in first number from user as a string
firstNumber =
JOptionPane.showInputDialog( "Enter first integer" );

// read in second number from user as a string
secondNumber =
JOptionPane.showInputDialog( "Enter second integer" );

// convert numbers from type String to type int
number1 = Integer.parseInt( firstNumber );
number2 = Integer.parseInt( secondNumber );

// add the numbers
sum = number1 + number2;
cha=number1-number2;
ji=number1*number2;
shang=number1/number2;
// display the results
JOptionPane.showMessageDialog(
null, "The sum is " + sum, "Results",
JOptionPane.PLAIN_MESSAGE );
JOptionPane.showMessageDialog(
null, "The cha is " + cha, "Results",
JOptionPane.PLAIN_MESSAGE );
JOptionPane.showMessageDialog(
null, "The ji is " + ji, "Results",
JOptionPane.PLAIN_MESSAGE );
JOptionPane.showMessageDialog(
null, "The shang is " + shang, "Results",
JOptionPane.PLAIN_MESSAGE );
System.exit( 0 ); // terminate the program
}
}