#多线程---全局变量---共享全局变量
#多线程可以对全局变量进行修改,修改后的结果会影响下一个线程
#进程不可以共享全局变量,子进程是复制父进程的全局变量,修改后互不影响
from threading import Thread
import time,random
g_num = 100
def work1():
global g_num
for i in range(3):
g_num += 1
time.sleep(random.random())
print("in work1,g_num=%d"%g_num)
def work2():
global g_num
for i in range(3):
g_num += 1
time.sleep(random.random())
print("in work2,g_num=%d"%g_num)
if __name__ == "__main__":
# work1()
# work2()
# print("主线程g_num%d"%g_num)
t1 = Thread(target=work1)
t2 = Thread(target=work2)
t1.start()
t2.start()
# print("主线程g_num%d" % g_num)
