using System.Collections.Generic;
static double f1(double a, double b, double c, double x)
else if (x > 0 && b == 0)
static double f2(double a, double b, double c, double x)
if (!(x < 0 && b != 0) && !(x > 0 && b == 0))
static void g1(double a, double b, double c, double x, ref double y)
else if (x > 0 && b == 0)
static void g2(double a, double b, double c, double x, ref double y)
if (!(x < 0 && b != 0) && !(x > 0 && b == 0))
static void h1(double a, double b, double c, double x, out double y)
else if (x > 0 && b == 0)
static void h2(double a, double b, double c, double x, out double y)
if (!(x < 0 && b != 0) && !(x > 0 && b == 0))
public static void Main(string[] args)
System.Console.Write("a = ");
double a = Convert.ToDouble(System.Console.ReadLine());
System.Console.Write("b = ");
double b = Convert.ToDouble(System.Console.ReadLine());
System.Console.Write("c = ");
double c = Convert.ToDouble(System.Console.ReadLine());
System.Console.Write("x = ");
double x = Convert.ToDouble(System.Console.ReadLine());
System.Console.WriteLine("F1 = " + f1(a,b,c,x));
System.Console.WriteLine("F2 = " + f2(a,b,c,x));
System.Console.WriteLine();
System.Console.WriteLine("G1 = " + y1);
System.Console.WriteLine("G2 = " + y2);
System.Console.WriteLine();
System.Console.WriteLine("H1 = " + z1);
System.Console.WriteLine("H2 = " + z2);
System.Console.WriteLine();