初学Java 从控制台读取输入

代码 

import java.util.Scanner;
public class ComputeArea {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
System.out.print("Enter a number for radius: ");
double radius = input.nextDouble();
double area;
area = radius * radius * 3.14159;
System.out.println("The area for the circle of radius " + radius + " is " + area);
}

}