# from machine import Pin
# import utime

# def light(p):
#     led=Pin(p,Pin.OUT)
#     led.value(1)
#     if p==1 or p==7 or p==11 or p==17:
#         utime.sleep(0.75)
#     else:
#         utime.sleep(2)
#     led.value(0)
#     utime.sleep(0.25)



# while True:
#     for i in range(0,3):
#         light(i)
#     for i in range(10,13):
#         light(i)
#     for i in range(6,9):
#         light(i)
#     for i in range(16,19):
#         light(i)
        
from machine import Pin
import utime

traffic1 = [0,1,2]
traffic2 = [10,11,12]
traffic3 = [6,7,8]
traffic4 = [16,17,18]

system = [traffic1, traffic2, traffic3, traffic4]

def traffic():
    for i in range(len(system)):
        yellow = Pin(system[i][1], Pin.OUT)
        yellow.value(1)
        for j in range(len(system)):
            if i != j:
                red = Pin(system[j][0], Pin.OUT)
                red.value(1)
        utime.sleep(1)
        yellow.value(0)

        green = Pin(system[i][2], Pin.OUT)
        green.value(1)
        for j in range(len(system)):
            if i != j:
                red = Pin(system[j][0], Pin.OUT)
                red.value(1)
        utime.sleep(5)
        green.value(0)
        for j in range(len(system)):
            if i != j:
                red = Pin(system[j][0], Pin.OUT)
                red.value(0)


while True:
    traffic()


print("Hello, Pi Pico!")