using System;

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public class Program

    {

        public static void Main()

        {

            Random random = new Random();

            string[] userName = new string[5];

            int userNameIndex;

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            userNameIndex = 0;

            int[] password = new int[5];

            int passwordIndex;

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            passwordIndex = 0;

            for (userNameIndex = 0; userNameIndex <= 4; userNameIndex++)

            {

                int a;

                int b;

                int c;

                char x;

                char y;

                char z;

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                a = random.Next(26) + 65;

                b = random.Next(26) + 65;

                c = random.Next(26) + 65;

                x = (char)a;

                y = (char)b;

                z = (char)c;

                string s = Convert.ToString(x);

                string t = Convert.ToString(y);

                string u = Convert.ToString(z);

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                userName[userNameIndex] = s + t + u;

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            }

            for (passwordIndex = 0; passwordIndex <= 4; passwordIndex++)

            {

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                int def;

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                def = random.Next(800) + 100;

                password[passwordIndex] = def;

            }

            int i;

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            i = 0;

            Console.WriteLine("User, Pwd");

            for (i = 0; i <= 4; i++)

            {

                Console.WriteLine(userName[i] + ", " + password[i]);

            }

            string enteredName;

            int enteredPassword;

            int count;

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            count = 0;

            bool found = false;

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            while (count < 3 && found == false)

            {

                Console.WriteLine("Please enter your userName:");

                enteredName = Console.ReadLine();

                Console.WriteLine("Please enter your password:");

                enteredPassword = int.Parse(Console.ReadLine());

                userNameIndex = 0;

                while (userNameIndex < 5 && found == false)

                {

                    if (userName[userNameIndex] == enteredName && password[userNameIndex] == enteredPassword)

                    {

                        found = true;

                    }

                    else

                    {

                        userNameIndex = userNameIndex + 1;

                    }

                }

                count = count + 1;

            }

            if (found == true)

            {

                Console.WriteLine("Welcome to the System.");

            }

            else

            {

                Console.WriteLine("Sorry.  Access denied.");

            }

        }

    }

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