simple java(十一)---application(２)

Write an application that asks the user to enter two integer numbers and prints the sum, difference, product and quotient of the numbers.

solution:其實只不過寫一個用對話框的方式來叫人入2個數字,之後電腦會自動計算它們的sum, difference, product and quotient的程式.如下.

import javax.swing.JOptionPane;

public class Calculate {

public static void main( String args[] ){

String firstNumber, secondNumber;

int number1, number2;

int sum, product, difference;double quotient;

firstNumber = JOptionPane.showInputDialog("Enter first integer:" );

secondNumber = JOptionPane.showInputDialog("Enter second integer:" );

number1 = Integer.parseInt( firstNumber );

number2 = Integer.parseInt( secondNumber );

sum = number1 + number2;

product = number1 * number2;

difference = number1 - number2;

quotient = (double) number1 / number2;

JOptionPane.showMessageDialog( null,"The sum is " + sum,

"Sum",JOptionPane.PLAIN_MESSAGE );

JOptionPane.showMessageDialog( null,"The product is " + product, "Product",JOptionPane.PLAIN_MESSAGE );

JOptionPane.showMessageDialog( null,"The difference is " + difference, "Difference",JOptionPane.PLAIN_MESSAGE );

JOptionPane.showMessageDialog( null,"The quotient is " + quotient, "Quotient",JOptionPane.PLAIN_MESSAGE );System.exit( 0 );}}

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Write an application that inputs from the user the radius of a circle and prints the circle’s diameter, circumference and area.

solution:其實係寫一個叫user入半徑..揾面積.直徑.圓周.如下：

import javax.swing.*;

public class range{

public static void main (String args[]){

String number1;

int radius,diameter;

double area,c,pi=3.1416;

number1=JOptionPane.showInputDialog ("enter the radius");

radius=Integer.parseInt(number1);

diameter=radius*2;

area=(radius*radius)*pi;

c= pi*diameter;

JOptionPane.showMessageDialog(null,"the diameter is"+ diameter+"\n"+"the area is"+area+"\n"+"the circumference is"+c);

System.exit(0);}}