from machine import Pin
from time import sleep

count = 0

entry = Pin(34, Pin.IN)
exit = Pin(35, Pin.IN)

green = Pin(23, Pin.OUT)
red = Pin(21, Pin.OUT)
yellow = Pin(19, Pin.OUT)
blue = Pin(5, Pin.OUT)

green.on()
red.off()
yellow.off()
blue.off()

while True:
    if entry.value() == 1:
        if count < 15:
            count += 1
            print("Cars:", count)
            yellow.on()
            sleep(0.2)
            yellow.off()
        sleep(0.3)

    if exit.value() == 1:
        if count > 0:
            count -= 1
            print("Cars:", count)
            blue.on()
            sleep(0.2)
            blue.off()
        sleep(0.3)

    if count == 15:
        green.off()
        red.on()
    else:
        green.on()
        red.off()