Ruby Multi User Login

# Structure      Username     Password   Age        Email
users_array = [["username1", "password1", 19, "email@gmail.com"],
               ["myuser2","mypass2",21,"Awesome.ninja@aol.co.uk"],
               ["Mr. P-teo", "secretPass", 23, "hidden_email@gmail.com"]]

user_array_rows = users_array.length

#input

print "Username: "
user_name = gets.chomp!

print "Password: "
user_password = gets.chomp!

if(user_name.length > 0 && user_password.length > 0)
    #move on to user validation

    count = 0
    #check user and pass agains stored user pass combos
    while count <= user_array_rows
        if(user_name == users_array[count][0] && user_password == users_array[count][1])
            count = user_array_rows + 1
            puts "Welcome to your account #{user_name}"
            logged_in = true
        end
        count += 1
    end
    #Check if logged in
    if(!logged_in)
        puts "Login attempt unsuccessful!"
    end
else
    #no use or pass entered.
    puts "Remember to enter both the username and password"
end