using System;

namespace Password_Validator
{
    class Program
    {
        static void Main(string[] args)
        {
            ValidatePassword(Console.ReadLine());
        }

        static void ValidatePassword(string password)
        {
            string validation = ValidatePassBetweenSixAndTenCharacters(password);
            if (validation != null)
            {
                Console.WriteLine(validation);
            }

            string validationTwo = ValidateContainsOnlyDigitsAndLetters(password);
            if (validationTwo != null)
            {
                Console.WriteLine(validationTwo);
            }

            string validationThree = ValidateHasLeastTwoDigits(password);
            if (validationThree != null)
            {
                Console.WriteLine(validationThree);
            }

            if (validation == null && validationTwo == null && validationThree == null)
            {
                Console.WriteLine("Password is valid");
            }
        }

        static string ValidatePassBetweenSixAndTenCharacters(string password)
        {
            int length = password.Length;
            string res = null;
            if(length < 6 || length > 10)
            {
                res = "Password must be between 6 and 10 characters";
            }
            return res;
        }

        static string ValidateContainsOnlyDigitsAndLetters(string password)
        {
            string res = null;

            for (int i = 0; i < password.Length; i++)
            {
                if(!char.IsLetterOrDigit(password[i]))
                {
                    res = "Password must consist only of letters and digits";
                    break;
                }
            }

            return res;
        }

        static string ValidateHasLeastTwoDigits(string password)
        {
            int counter = 0;
            string res = null;
            foreach (char c in password)
            {
                if (char.IsDigit(c))
                {
                    counter++;
                }

                if (counter == 2)
                {
                    break;
                }
            }

            if (counter < 2)
            {
                res = "Password must have at least 2 digits";
            }

            return res;
        }
    }
}