#include <iostream>
#include <vector>
#include <corecrt_math.h>
#include <iomanip>

bool GetData(double& A, double& B, double& C);
std::vector<std::pair<std::string, double>> Solve(double A, double B, double C);

int main()
{
	setlocale(LC_ALL, "ru-RU");

	double A, B, C;	

	if (GetData(A, B, C))
	{
		auto vec = Solve(A, B, C);

		for (int i = 0; i < vec.size(); ++i)
		{
			if (vec[0].second == INFINITY)
			{
				std::cout << vec[0].first << std::endl;
				break;
			}
			else
			{
				std::cout << vec[i].first << " = ";

				if (vec[i].second == static_cast<int>(vec[i].second))
				{
					std::cout << static_cast<int>(vec[i].second) << std::endl;
				}
				else
				{
					std::cout << std::fixed << std::setprecision(4) << vec[i].second << std::endl;
				}
			}
		}
	}
	else
	{
		std::cout << "Данные введены не коректно!\n";
		system("pause");
		return 0;
	}

	system("pause");
	return 0;
}

std::vector<std::pair<std::string, double>> Solve(double A, double B, double C)
{
	std::vector<std::pair<std::string, double>> vec(2);

	if (A == 0 && C == 0)
	{
		vec[0].first = "ЛЮБОЕ Х ЯВЛЯЕТСЯ РЕШЕНИЕМ УРАВНЕНИЯ";
		vec[0].second = INFINITY;
		return vec;
	}

	double diskr = ((pow(B, 2)) - (4 * A * C));
	if (diskr < 0)
	{
		vec[0].first = "НЕРАВЕНСТВО РЕШЕНИЙ НЕ ИМЕЕТ";
		vec[0].second = INFINITY;
		return vec;
	}
	else if (diskr == 0)
	{
		vec[0].first = "X1";
		vec[0].second = (((B * (-1)) + (sqrt(diskr))) / (2 * A));
		return vec;
	}
	else if (diskr > 0)
	{
		vec[0].first = "X1";
		vec[0].second = (((B * (-1)) + (sqrt(diskr))) / (2 * A));

		vec[1].first = "X2";
		vec[1].second = (((B * (-1)) - (sqrt(diskr))) / (2 * A));

		return vec;
	}
}

bool GetData(double& A, double& B, double& C)
{
	bool flag = false;

	std::cout << "A = ";
	if (std::cin >> A)
	{
		flag = true;
	}
	else
	{
		flag = false;
	}

	std::cout << "B = ";
	if (std::cin >> B)
	{
		flag = true;
	}
	else
	{
		flag = false;
	}

	std::cout << "C = ";
	if (std::cin >> C)
	{
		flag = true;
	}
	else
	{
		flag = false;
	}

	return flag;
}