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

using namespace std;

int main()
{
        float a, b, c, delta, x0, x1, x2;
        
        cout << "Cet algorithme calcule les solutions de l'équation a*x^2+b*x+c=0" << endl;
        cout << "Entrez a:";
        cin >> a;
        cout << "Entrez b:";
        cin >> b;
        cout << "Entrez c:";
        cin >> c;

        if (a == 0)
        {
                if (b != 0)
                {
                        x0 = -c / b;
                        cout << "x =" << x0 << endl;
                }
                else           // ici b = 0
                {
                        if (c == 0)
                        {
                                cout <<"infinite de solutions" << endl;
                        }
                        else
                        {
                                cout <<"aucune solution" << endl;
                        }                        
                }
        }
        else
        {
                delta = b*b-4*a*c;
                
                if (delta <0)
                {
                        cout <<"aucune solution" << endl;
                }
                else
                {
                        if (delta == 0)
                        {
                                x0=-b/(2*a);
                                cout << "x =" << x0 << endl;
                        }
                        else
                        {
                                x1 = (-b-sqrt(delta))/(2*a);
                                x2 = (-b+sqrt(delta))/(2*a);                       
                                cout << "Il y a 2 racines réelles x1 =" << x1 << " et x2 =" << x2 <<endl;
                        }
                }
        }
}