#include <iostream>
using namespace std;
void QuadraticEquation(double a, double b, double c)
{
	if (a == 0)
	{
		if (b == 0)
		{
			if (c == 0)
				cout << "Vo so nghiem";
			else cout << "Vo nghiem";
		}
		else
		{
			cout << "Phuong trinh co mot nghiem duy nhat x = :" << -c / b;
		}
	}
	else
	{
		double delta = b * b - 4 * a * c;
		if (delta > 0)
		{
			cout << "Phuong trinh co nghiem x1 = " << (-b + sqrt(delta)) / 2 * a;
			cout << endl;
			cout << "Phuong trinh co nghiem x2 = " << (-b - sqrt(delta)) / 2 * a;
		}
		else if (delta == 0)
			cout << "Phuong trinh co nghiem x = " << -b / 2 * a;
		else
			cout << "Phuong trinh vo nghiem";
	}
}
void main()
{
	double m, n, p;
	cout << "Nhap 3 so a,b,c:";
	cin >> m >> n >> p;
	QuadraticEquation(m, n, p);
}