quadratic.cpp

#include <iostream>
#include <iomanip>
#include <cmath>

void SolveQuadratic(int a, int b, int c) {
    //Установка точности вывода в 6 символов
    std::cout << std::setprecision(6);

    double eps = 1e-3;     // Погрешность при сравнении double
    double x1{0}, x2{0};
    if (a == 0 && b == 0 && c != 0) {
        std::cout << "no solutions";
        return;
    }
    if (a == 0 && b == 0 && c == 0) {
        std::cout << "infinite solutions";
        return;
    }
    if(b != 0 && a == 0){
        x1 = -c / static_cast<double>(b);
        std::cout << x1;
        return;
    }
    
    long long d = static_cast<long long>(b) * b - 4 * static_cast<long long>(a) * c;
    if(d < 0){
        std::cout << "no solutions";
        return;
    }

    x1 = (-b + sqrt(d)) / (2*a);
    x2 = (-b - sqrt(d)) / (2*a);
    if((x1 - x2) < eps){
        std::cout << x1;
    }
    else{
        if(x1 > x2){
            std::swap(x1, x2);
        }
        std::cout << x1 << " " << x2;
    }
}