#include <iostream>
#include <cmath>
using namespace std;

double a;
double b;
double c;
double x;

int main() {
    cout << "a: ";
    cin >> a;
    cout << "b: ";
    cin >> b;
    cout << "c: ";
    cin >> c;
    if((b*b - 4*a*c) >= 0) {
        x = ( -b + sqrt(b*b - 4*a*c) ) / (2*a);
        cout << "x1 = " << x << endl;
        x = ( -b - sqrt(b*b - 4*a*c) ) / (2*a);
        cout << "x2 = " << x << endl;
    }
    else {
        cout << "D < 0" << endl;
    }

    return 0;
}