using System.Collections.Generic;
using System;
public static class QuadraticFunction
{
/// <summary>
/// Generate roots of quadratic function from given parameters A, B, C.
///
/// <param name="a">Coefficient A of quadratic function</param>
/// <param name="b">Coefficient B of quadratic function</param>
/// <param name="c">Coefficient C of quadratic function</param>
/// <returns> Collection of roots
/// where delta = b^2 - 4ac
/// 2 roots is delta > 0 (-b + sqrt(delta) / 2a), (-b - sqrt(delta) / 2a),
/// 1 root if delta = 0 (-b / 2a)
/// empty collection if delta < 0
/// <example>
/// a = 2, b = -8, c = 11, result: {}
/// a = 1, b = -2, c = -8, result: {-2, 4}
/// a = 1, b = 0, c = 0, result: {0}
/// </example>
/// <exception cref="ArgumentException">Thrown if parameter A = 0</exception>
/// </returns>
/// </summary>
public static IEnumerable<double> Calculate(double a, double b, double c)
return default;
}
public class Program
public static void Main()
//for example:
Test_Delta_Equal_0();
public static void Test_Delta_Equal_0()