float data(float a[3][5], int n)
{
	// n = 3
	float x = 1, y = 1, z = 1, f, v = 1,m = 1,o = 1;
	int k = 2 , l = 0;
	float B[3][5];

	for (int i = 0; i < n; i++)
	{
		for (int j = 0; j < n; j++)
			B[i][j] = a[i][j];
	}

	for (int i = 0; i < n; i++)
	{
		B[i][3] = a[i][0];
		B[i][4] = a[i][1];
	}


	if (n == 2)
	{
		f = (a[0][0] * a[1][1]) - (a[0][1] * a[1][0]);
	}
	else
	{
		for (int j = 0; j < n; j++)
		{

			x *= B[j][j];
			y *= B[j][j + 1];
			z *= B[j][j + 2];

			v *= B[j][k];
			m *= B[j][k + 1];
			o *= B[j][k + 2];
			k -= 1;

		}

		f = x + y + z - v - m - o;
	}

	return f;
}

void hpt2()
{
	float a[3][5]; float b[3][3]; float c[3][1]; float f;
	float a1[3][5]; float a2[3][5]; float a3[3][5];
	float x, y, z;
	cout << "Hay nhap gia tri nhu duoi day: " << endl;
	cout << "a[0][0]x + a[0][1]y + a[0][2] = c0" << endl;
	cout << "a[1][0]x + a[1][1]y + a[1][2] = c1" << endl;
	cout << "a[2][0]x + a[2][1]y + a[2][2] = c2" << endl;
	cout << endl;

	for (int i = 0; i <= 2; i++)
	for (int j = 0; j <= 2; j++)
	{
		cout << "Hay nhap a[" << i << "]" << "[" << j << "]: ";
		cin >> a[i][j];
	}

	for (int i = 0; i <= 2; i++)
	{
		cout << "Hay nhap c" << i << ": ";
		cin >> c[i][0];
	}

	f = data(a, 3);

	if (f == 0)
		cout << "He pt vo nghiem" << endl;
	else
	{
	for (int i = 0; i <= 2; i++)
	for (int j = 0; j <= 2; j++)
	{
		a1[i][j] = a[i][j];
		a2[i][j] = a[i][j];
		a3[i][j] = a[i][j];
	}


	for (int i = 0; i <= 2; i++)
	{
		a1[i][0] = c[i][0];
		a2[i][1] = c[i][0];
		a3[i][2] = c[i][0];
	}

	x = data(a1, 3) / f;
	y = data(a2, 3) / f;
	z = data(a3, 3) / f;

	cout << "He phuong trinh co nghiem la: " << endl;
	cout << "x = " << x << endl;
	cout << "y = " << y << endl;
	cout << "z = " << z << endl;
	}
}

void hpt1()
{
	float f, x , y;
	float a[3][5]; float b[2][2]; float c[2][1];
	float a1[3][5]; float a2[3][5];
	cout << "Hay nhap gia tri nhu duoi day: " << endl;
	cout << "a[0][0]x + a[0][1]y = c0" << endl;
	cout << "a[1][0]x + a[1][1]y = c1" << endl;
	cout << endl;

	for (int i = 0; i <= 1; i++)
	{

		for (int j = 0; j <= 1; j++)
		{
			cout << "Hay nhap a[" << i << "]" << "[" << j << "]: ";
			cin >> a[i][j];
		}

	}
	for (int i = 0; i <= 1; i++)
	{
		cout << "Hay nhap c" << i << ": ";
		cin >> c[i][0];
	}

	f = data(a, 2);

	if (f == 0)
		cout << "He pt vo nghiem" << endl;
	else
	{
		for (int i = 0; i <= 1; i++)
		for (int j = 0; j <= 1; j++)
		{
			a1[i][j] = a[i][j];
			a2[i][j] = a[i][j];
		}


		for (int i = 0; i <= 1; i++)
		{
			a1[i][0] = c[i][0];
			a2[i][1] = c[i][0];
		}

		x = data(a1, 2) / f;
		y = data(a2, 2) / f;

		cout << "He phuong trinh co nghiem la: " << endl;
		cout << "x = " << x << endl;
		cout << "y = " << y << endl;
	}

}