public static void Main()
Console.WriteLine("Zadej cislo ");
string textCislo = Console.ReadLine();
bool jeCislo = double.TryParse (textCislo, out cislo);
Console.WriteLine("Toto neni cislo, prosím zadej cislo: ");
textCislo = Console.ReadLine();
jeCislo = double.TryParse (textCislo, out cislo);
Console.WriteLine("Zadal jsi " + cislo + " dekuji!");