软考知识-Python实现PV操作

防盗标识：本文源文地址，未授权禁止转载https://blog.csdn.net/weixin_44331765/article/details/122784219

import threading, time
import random

s1 = threading.Semaphore(value=1)
s2 = threading.Semaphore(value=0)
pro = 0
con = 0
cache = 0
product_list = ['小米手机','华为手机','vivo','电脑','手环']

def producer():
    global pro,s1,s2,cache
    count = 4
    for i in range(len(product_list)):
        print('生产者：开始',s1,s2)
        pro = random.choice(product_list)
        print('生产者：生产：',pro)
        # 执行P(s2)操作
        s1.acquire()
        cache = pro
        print('生产者：送进去产品',pro,'缓存中产品：',cache)
        # 执行V(s1)操作
        s2.release()
        print('生产者：结束----')
        count -= 1
        time.sleep(0.5)

def consumer():
    global con,s1,s2,cache
    count = 5
    while count:
        print('消费者：等待----',s1,s2)
        # 执行P(s2)操作
        s2.acquire()
        con = cache
        cache = '空'
        print('消费者：缓存取出产品：',con,'缓存中产品个数：',cache)
        # 执行V(s1)操作
        s1.release()
        print('消费者：消费产品', con)
        print('消费者：结束----')
        count -= 1

if __name__ == '__main__':
    t1 = threading.Thread(target=producer)
    t2 = threading.Thread(target=consumer)
    t1.start()
    t2.start()