package cn.Douzi.Lab7_4;


public class Triangle {
    
    int a, b, c;

    public Triangle(int a, int b, int c) {
        super();
        this.a = a;
        this.b = b;
        this.c = c;
    }
    
    int getArea() throws Exception {
        
        if (a + b <= c || a + c <= b || b + c <= a) {
            
 
throw new IllegalArgumentException("兩邊之和大於第三邊");
        }
        else {
            int p = (a + b + c) / 2;
            return (int)Math.sqrt(p * (p - a) * (p - b) * (p - c));
        }
        
    }
    
}

package cn.Douzi.Lab7_4;

public class Lab4 {

    public static void main(String[] args) {
        
 
// TODO Auto-generated method stub
        
        Triangle tri = new Triangle(5, 1, 4);
        
        try {
            int area;
            area = tri.getArea();
            System.out.println("面積: " + area);            
        } catch (Exception e) {
            // TODO Auto-generated catch block
 

            e.printStackTrace();
        } finally {
            
        }
    }

}

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