JAVA学习笔记-基本输入输出示例

package javaapplication1;

import javax.swing.JOptionPane;
import java.util.Scanner;

public class JavaApplication1 {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
System.out.print("Please input a double:");

double radius = input.nextDouble();
double area = 3.1415 * radius * radius;

System.out.println("Area is :" + area);
}
}