#!/usr/bin/env python

# -*- coding:utf-8 -*-

__author__ = 'MFC'

__time__ = '2019-07-15 11:32'

"""

lesson 4

线性结构：

1.内存连续

2.下标访问

cd ~/Python3Demo/pw_python/algorithm

pytest array_and_list.py

ref:

https://pegasuswang.github.io/python_data_structures_and_algorithms/02_%E6%95%B0%E7%BB%84%E5%92%8C%E5%88%97%E8%A1%A8/array_and_list/

"""

from array import array

arr = array('u', 'asdf')

print(arr)

print(arr[0])

print(arr[1])

class Array(object):

def __init__(self, size=32):

self._size = size

self._items = [None] * size

def __getitem__(self, index):

return self._items[index]

def __setitem__(self, index, value):

self._items[index] = value

def __len__(self):

return self._size

def clear(self, value=None):

for i in range(len(self._items)):

self._items[i] = value

def __iter__(self):

for item in self._items:

yield item

def test_array():

size = 10

a = Array(size)

a[0] = 1

assert a[0] == 1

a.clear()

assert a[0] is None