W3School TIY Editor

public class Main { public static void main(String[] args) { // 创建整型变量 int length = 4; int width = 6; int area; // 计算矩形面积 area = length * width; // 打印变量 System.out.println("长度为: " + length); System.out.println("宽度为: " + width); System.out.println("矩形面积为: " + area); } }