using System;

public class Program

{

    public static void Main()

    {

        string password = "!!@M4r10";

        if(ValidatePassword(password)){

            Console.WriteLine("Berhasil");

        }else{

            Console.WriteLine("gagal");

        }

    }

    static bool ValidatePassword( string password )

    {

      const int MIN_LENGTH =  8 ;

      const int MAX_LENGTH = 15 ;

​

      if ( password == null ) throw new ArgumentNullException() ;

​

      bool meetsLengthRequirements = password.Length >= MIN_LENGTH && password.Length <= MAX_LENGTH ;

      bool hasUpperCaseLetter      = false ;

      bool hasLowerCaseLetter      = false ;

      bool hasDecimalDigit         = false ;

​

      if ( meetsLengthRequirements )

      {

        foreach (char c in password )

        {

          if      ( char.IsUpper(c) ) hasUpperCaseLetter = true ;

          else if ( char.IsLower(c) ) hasLowerCaseLetter = true ;

          else if ( char.IsDigit(c) ) hasDecimalDigit    = true ;

        }

      }

​

      bool isValid = meetsLengthRequirements

                  && hasUpperCaseLetter

                  && hasLowerCaseLetter

                  && hasDecimalDigit

                  ;

      return isValid ;

​

    }

}