import java.util.Scanner;
public class Test{
public static void main(String[] args){
double a, b, c; //三角形三条边
Scanner sc = new Scanner(System.in);
System.out.println("请输入三角形的三条边长(回车键输入下一位):");
a = sc.nextDouble();
b = sc.nextDouble();
c = sc.nextDouble();
Triangle angle = new Triangle(a, b, c);
if(angle.isTriangle()){
System.out.println("三角形的周长是:" + angle.periTriangle());
System.out.println("三角形的面积是:" + angle.areaTriangle());
}else
System.out.println("这三个边长不能组成三角形:" + a + " " + b + " " + c);
sc.close();
}
}
class Triangle{
private double a, b, c;
public Triangle(double a, double b, double c){
this.a = a;
this.b = b;
this.c = c;
}
public boolean isTriangle(){ //判断是否能够组成三角形
if( a + b > c && a + c > b && b + c > a){ return true;}
else
return false;
}
public double periTriangle(){ //周长
return a + b + c;
}
public double areaTriangle(){ //面积,用海伦公式计算
double area = 0.0, temp = 0.0;
temp = 0.5 * (a + b + c);
area = Math.sqrt(temp * (temp -a) * (temp -b) * (temp -c));
return area;
}
}
可以做