[Python]多线程threading函数方法--计算5!+4!+3!+2!+1!

#coding=utf8
'''
def singles():
sum = 0
for i in range(1,6):
t=reduce(lambda x,y:x*y,range(1,i+1))
sum +=t
return sum
print singles()
'''
#多线程实现，一下子启动5个线程，去计算1-5的阶乘，一个全局变量sum把结果加到一起
import threading,time

sum = 0
lock = threading.Lock()
def single(i):
global sum,lock
lock.acquire()
t=reduce(lambda x,y:x*y,range(1,i+1))
sum = sum + t
print threading.currentThread().getName(),t
lock.release()

def main():
global sum
for i in range(1,6):
threading.Thread(target=single,args=(i,),name='Thread'+str(i)).start()
time.sleep(1)
print sum

if __name__=='__main__':
main()