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：