Computer craft password door

password = "1234"
side = "left"
opentime = 5
invertedSignal = false
local fail = 0

while true do
    term.clear()
    term.setCursorPos(1,1)
    print() -- empty line
    write("  Password: ")
    input = read("*")
    if input == password then
        print("Access granted!")
        if invertedSignal then
            rs.setOutput(side, false)
            sleep(opentime)
            rs.setOutput(side, true)
        else
            rs.setOutput(side, true)
            sleep(opentime)
            rs.setOutput(side, false)
        end
    else
        fail = fail+1
        print("Access denied!")
        if fail == 3 then
            print("  Failed 3 times")
            print("  Rebooting...")
            sleep(2)
            os.shutdown()
        end
    end
    sleep(0.2)
end