Mọi người giúp em với chương trình chạy rồi nhưng sai kết quả

#include <iostream>
#include <conio.h>
#include <math.h>

using namespace std;

class ToaDo{
	
	private:
		
		int x,y;
		char z;
		
	public:
		void Input();
		void Output();
		int Getx();
		int Gety();
		int TestD();
		int TestTG();

		
};
class Tam{
	
	private:
		
		ToaDo A, B, C;
	public:
		
		void Input_d();
		void Output_d();
		double Dodai(ToaDo a, ToaDo b);
		int TestDD();
		void TestTam();
		double Dien();
};


int main(){
	
	ToaDo t;
	Tam d;
    int count = 0;

	do{
		
		d.Input_d();
		
	}while(t.TestD());
	
	cout << "Toa do cua ba diem thoa man: " << endl;
	
	
	d.Output_d();
	
	cout << "Tam giac.
";
	
	d.TestTam();
	
	cout << "Dien tich tam giac: " << d.Dien();
	
	
	system("pause");
	
	return 0;
}

void ToaDo :: Input(){
	ToaDo t;
	
	cout << "Diem: ";
	fflush(stdin);
	cin  >> z;
	
	cout << "Nhap vao toa do x:";
	cin  >> x;
	
	cout << "Nhap vao toa do y: ";
	cin  >> y;
	
	t.TestD();
}
void ToaDo :: Output(){
	
	cout << z << "(" << x << ", " << y << ")" << endl;
	
}

int ToaDo :: Getx(){
	
	return x;
}
int ToaDo :: Gety(){
	
	return y;
}
int ToaDo :: TestD(){
	
	if(x < 0 || y < 0){
		
		return 0;
	}
	
}
//--------- ham lien quan den dinh cua tam giac-----
void Tam :: Input_d(){
	
	A.Input();
	B.Input();
	C.Input();
	
}
void Tam :: Output_d(){
	
	A.Output();
	B.Output();
	C.Output();

	
}
double Tam :: Dodai(ToaDo a, ToaDo b){
	
	double canh = sqrt( pow((a.Getx() - b.Getx()),2) + pow((a.Gety() - b.Gety()),2) );
	
	return canh;
}

int Tam ::  TestDD(){
	
	ToaDo a, b, c;
	Tam t;
	
	double ab = t.Dodai(a, b);
	double bc = t.Dodai(b, c);
	double ac = t.Dodai(a, c);
	
	if(ab + bc <= ac || ac + bc <= ab || ab + ac <= bc ){
		
		return 0;
	}
	
}

void Tam :: TestTam(){
	
	Tam d;
	
	ToaDo a, b, c;
	
	double ab, bc, ac;
	
	ab = d.Dodai(a, b);
	bc = d.Dodai(b, c);
	ac = d.Dodai(a, c);
	
	if(ab == bc){
		
		if(ab*ab + bc*bc == ac*ac){
			
			cout << "Tam giac vuong can tai b." << endl;
			
		}else{
			
			cout << "Tam giac can tai b." << endl;
			
		}
		
	}else if(ab == ac){
		
		if(ab*ab + ac*ac == bc*bc){
			
			cout << "Tam giac vuong can tai a." << endl;
			
		}else{
			
			cout << "Tam giac can tai a." << endl;
			
		}
    }
    else{
		
		if(ac*ac + bc*bc == ab*ab){
			
			cout << "Tam giac vuong can tai c." << endl;
			
		}else{
			
			cout << "Tam giac can tai c." << endl;
			
		}
		
	}
	

}
double Tam :: Dien(){
	
	Tam d;
	ToaDo a,b,c;
	
	double s;
	
		double ab = d.Dodai(a, b);
		double bc = d.Dodai(b, c);
		double ac = d.Dodai(a, c);
		
		double p = (ab+bc+ac)/2.0;
		
		s = sqrt(p*(p-ab)*(p-ac)*(p-bc));
	
	return s;
}