¿Creen que se puede hacer escribir más corto el programa?

Question

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading;
using System.Threading.Tasks;

namespace SoloLearn
{
class Program
{
static void Main(string[] args)
{
string password = Console.ReadLine();
char[] notAllowedSymbols = { '!', '#', '

Answer 1

You could use foreach like this:
foreach(var symbol in notAllowedSymbols)

or Any like this:
if notAllowedSymbols.Any(s => password.Contains(s))

Answer 2

I guess you have to output something for a valid password as well

Answer 3

In fact it is all that they ask me in the task, I only had the doubt if the shorter code can be written