#Author:qinjiaxi
'''本程序计算各种循环的时间效率'''
from timeit import Timer
def test1(n):
li = []
for i in range(n*1000):
li = li +[i]
return li
def test2(n):
li = []
li = [i for i in range(n*1000)]
return li
def test3(n):
li = []
for i in range(n*1000):
li.append(i)
return li
def test4(n):
li = []
ii = list(range(n*1000))
return li
t1 = Timer('test1(10)', 'from __main__ import test1')
print('+:', t1.timeit(1000))
t2 = Timer('test2(10)', 'from __main__ import test2')
print('[]:', t2.timeit(1000))
t3 = Timer('test3(10)', 'from __main__ import test3')
print('append:', t3.timeit(1000))
t4 = Timer('test4(10)', 'from __main__ import test4')
print('range:', t4.timeit(1000))