import time
from time import sleep
from machine import Pin as p
time.sleep(0.1) # Wait for USB to become ready

print("Hello, Pi Pico!")
led1=p(0, p.OUT)
led2=p(1, p.OUT)
led3=p(2, p.OUT)
led4=p(3, p.OUT)

while True:
    ##for i in range(4):
    ##    leds[i].value(1)
    ##    sleep(0.5)
    ##    for j in range(4):
    ##        leds[j].value(1)
    ##        sleep(0.5)
    ##        for k in range(4):
    ##            leds[k].value(1)
    ##            sleep(0.5)
    ##            for l in range(4):
    ##               leds[l].value(1)
    ##                sleep(0.5)
    led1.value(0)
    led2.value(0)
    led3.value(0)
    led4.value(0)
    print("0")
    sleep(0.5)

    led1.value(1)
    led2.value(0)
    led3.value(0)
    led4.value(0)
    print("1")
    sleep(0.5)
    led1.value(0)
    led2.value(1)
    led3.value(0)
    led4.value(0)
    print("2")
    sleep(0.5)
    led1.value(1)
    led2.value(1)
    led3.value(0)
    led4.value(0)
    print("3")
    sleep(0.5)
    led1.value(0)
    led2.value(0)
    led3.value(1)
    led4.value(0)
    print("4")
    sleep(0.5)
    led1.value(1)
    led2.value(0)
    led3.value(1)
    led4.value(0)
    print("5")
    sleep(0.5)
    led1.value(0)
    led2.value(1)
    led3.value(1)
    led4.value(0)
    print("6")
    sleep(0.5)
    led1.value(1)
    led2.value(1)
    led3.value(1)
    led4.value(0)
    print("7")
    sleep(0.5)
    led1.value(0)
    led2.value(0)
    led3.value(0)
    led4.value(1)
    print("8")
    sleep(0.5)
    led1.value(1)
    led2.value(0)
    led3.value(0)
    led4.value(1)
    print("9")
    sleep(0.5)
    led1.value(0)
    led2.value(1)
    led3.value(0)
    led4.value(1)
    print("10")
    sleep(0.5)
    led1.value(1)
    led2.value(1)
    led3.value(0)
    led4.value(1)
    print("11")
    sleep(0.5)
    led1.value(0)
    led2.value(0)
    led3.value(1)
    led4.value(1)
    print("12")
    sleep(0.5)
    led1.value(1)
    led2.value(0)
    led3.value(1)
    led4.value(1)
    print("13")
    sleep(0.5)
    led1.value(0)
    led2.value(1)
    led3.value(1)
    led4.value(1)
    print("14")
    sleep(0.5)
    led1.value(1)
    led2.value(1)
    led3.value(1)
    led4.value(1)
    print("15")
    sleep(0.5)