Ghast Counter

mon = peripheral.wrap("back")
mon.setBackgroundColor(colors.lime)
mon.setTextScale(5)
mon.clear()

file = fs.open("Count", "r")
x = file.readLine()
file.close()

mon.setCursorPos(1,2)
mon.setTextColor(colors.black)
mon.write(" Ghast Count: ")
mon.setCursorPos(1,3)
mon.write("    "..x.."       ")

while true do
    if rs.getInput("left") then
        x = x + 1
        file = fs.open("Count", "w")
        file.write(x)
        file.close()
        mon.setCursorPos(1,3)
        mon.write("    "..x.."       ")
        sleep(3)
    end
sleep(0.5)
end