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1.递归访问目录： 且目录中嵌套目录，有层次的列出给定目录中所有的文件和文件夹

2.定义一个嵌套函数，

3.定义一个递归函数：打印斐波那契数列

4.对列表进行排序: list_data = ["grape", "peach", "berry", "pineapple", "apple", "strayberry", "watermelon"]

5.利用map函数： 计算三个列表，相同位置元素之和list1 = [1, 2, 3]list2 = [4, 5, 6]list3 = [7, 8, 9]

6.利用filter函数过滤列表中所有带a的字符串list_data = ["grape", "what", "which", "you", "friend", "am"]

7.利用reduce计

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1.递归访问目录： 且目录中嵌套目录，有层次的列出给定目录中所有的文件和文件夹

先在D盘新建一个目录data,data目录中包含一个data1文件夹和data.txt文件，data1文件夹中包含data2和data.xsl，data2文件夹中包含data3和data.doc，data2文件夹中包含data3.txt

import os
 
 
def list_dir_content(dir_path, count=0):   
    for file_name in os.listdir(dir_path):
        sub_path = os.path.join(dir_path, file_name)
        if os.path.isdir(sub_path):
            print(count * "\t" + file_name)
            sub_count = count + 1
            list_dir_content(sub_path, sub_count)
        if os.path.isfile(sub_path):
            print(count * "\t" + file_name)
 
list_dir_content("D:\\test")
print(os.getcwd())
 

data.txt.txt
data1
	data.xls.xls
	data2
		data.doc.doc
		data3
			datat3.txt.txt
D:\Python\python_code

2.定义一个嵌套函数，

外层函数打印this is outing function
内层函数功能:打印This is inner function

def outing():
    print('this is outing fuction')
    def inner():
        print('this is inner fuction')
    inner()
outing()
 

this is outing fuction
this is inner fuction

3.定义一个递归函数：打印斐波那契数列

F[n]=F[n-1]+F[n-2](n>=2,F[0]=0,F[1]=1)

def Fibonacci_series(n):
    a = [0]
    if n > 1:
        a = [0, 1]
        for i in range(n-2):
            a.append(a[-2] + a[-1])
    return a
print(Fibonacci_series(10))
 

[0, 1, 1, 2, 3, 5, 8, 13, 21, 34]

4.对列表进行排序: list_data = ["grape", "peach", "berry", "pineapple", "apple", "strayberry", "watermelon"]

排序规则：按照最后一个字符进行排序，如果最后一个字符相等，按照第一个字符排序

def get_three_char(str_data):
    return str_data[-1], str_data[0]      #按照最后一个字母排序,若相同比较倒数第一个
list_data =  ['grape','peach','berry','pineapple','apple','strayberry','watermelon']
list_data.sort(key=get_three_char)
print(list_data)
 

['apple', 'grape', 'pineapple', 'peach', 'watermelon', 'berry', 'strayberry']
 

5.利用map函数： 计算三个列表，相同位置元素之和
list1 = [1, 2, 3]
list2 = [4, 5, 6]
list3 = [7, 8, 9]

list1 = [1, 2, 3]
list2 = [4, 5, 6]
list3 = [7, 8, 9]
map_obj = map(lambda x, y, z: x+y+z, list1, list2, list3)
print(list(map_obj))
 

[12, 15, 18]
 

6.利用filter函数过滤列表中所有带a的字符串
list_data = ["grape", "what", "which", "you", "friend", "am"]

list_data = ['grape', 'what', 'which', 'you', 'friend', 'am']
fil_obj = filter(lambda x: 'a' not in x, list_data)
print(list(fil_obj))
 

['which', 'you', 'friend']
 

7.利用reduce计

from functools import reduce
red_v = reduce(lambda x, y: x+y, list(range(101)))
print(red_v)
 

5050
 

算1 + 2 + 3...+ 100之和