第一个Java程序

class Triangle{int a = 10, b = 20, c = 25;int Zhouchang(){return a + b + c;}double Area(){double p = Zhouchang() / 2.0;return Math.sqrt(p * (p - a) * (p - b) * (p - c));}}public class hello{public static void main(String[] args){Triangle a = new Triangle();System.out.printf("%d\t%f\n", a.Zhouchang(), a.Area());}}

运行结果：