public static void TrapezeAreaChoice() { Menu.TrapezeAreaMenu(); string input = Console.ReadLine(); switch (input) { case "1": Trapeze.TrapezAreaFormula1(); break; case "2": Trapeze.TrapezAreaFormula2(); break; case "3": Trapeze.TrapezAreaFormula3(); break; case "4": break; default: Console.WriteLine("Wrong Input!"); TrapezeAreaChoice(); break; } }