Python(十)——拼接字符串的效率对比

Python(十)——拼接字符串的效率对比

import time

def str1():
    time0 = time.time()
    a = ''
    for i in range(10000):
        a+='str'

    time1 = time.time()
    print(time1-time0)

def str2():
    time0 = time.time()
    list1 = []
    for i in range(10000):
        list1.append('str')
    ''.join(list1)
    time1 = time.time()
    print(time1-time0)

if __name__=='__main__':
    str1() #0.003031492233276367
    str2() #0.0019953250885009766

原因：
str1()创建了10000次的对象，比str2()创建的对象要多得多得多，所以执行效率低。