练习一:写函数,验证用户名是否在文件data.txt中存在,如果存在返回 True,否则返回False
答:
# 构造数据
with open('data.txt', mode='w', encoding='utf-8') as f:
f.write('1|alex|123123
')
f.write('2|eric|rwerwe
')
f.write('3|wupeiqi|ppp
')
# 函数定义
def name_judge(name):
data_list = []
flag = False
with open('data.txt', mode='r', encoding='utf-8') as f:
for item in f:
s, n, p = item.strip().split('|')
data_dict = {'serial': s, 'name': n, 'pwd': p}
data_list.append(data_dict)
for i in data_list:
if name == i['name']:
flag = True
return flag
# 函数调用
while True:
char = input('请输入:')
result = name_judge(char)
print(result)
练习二:写函数,在函数内部生成如下规则的列表[1,1,2,3,5,8,13,21,34,55,....] (斐波那契数列),并返回。
要求:函数可接收一个参数,用于指定列表中元素最大不可以超过范围
答:
# 函数定义
def fuc(num):
result = []
while True:
if len(result) == 0:
result.append(1)
elif len(result) == 1:
result.append(1)
else:
val = result[-1] + result[-2]
if val > num:
break
result.append(val)
return result
# 函数调用
v = fuc(100)
print(v)
练习三:写函数,返回两个数字中大的那个
答:
func = lambda n1, n2: n1 if n1 > n2 else n2
v = func(1, 2)
print(v)
练习四:看代码,写结果
USER_LIST = []
func = lambda x: USER_LIST.append(x)
v = func('alex')
print(v)
print(USER_LIST)
答:
print(v):None
print(USER_LIST):['alex']
练习五:写函数,实现数据分页
要求:
1.每页显示10条数据
2.让用户输入要查看的页码
答:
# 构建数据
USER_LIST = []
for i in range(1, 836):
temp = {'name': '张三-%s' % i, 'email': '123%s@qq.com' % i}
USER_LIST.append(temp)
# 数据总量
total_count = len(USER_LIST)
# 每页展示数量
per_page_count = 20
# 计算最大页码数
max_page_num, v = divmod(total_count, per_page_count)
if v != 0:
max_page_num += 1
# 分页程序:利用列表切片功能实现
while True:
page_num = input('请输入要查看的页码:')
if int(page_num) in range(1, max_page_num + 1):
start_index = (int(page_num) - 1) * per_page_count
end_index = int(page_num) * per_page_count
data = USER_LIST[start_index:end_index]
for item in data:
print(item)
else:
print('页码不合法,可查看范围[%s - %s]' % (1, max_page_num))
continue
练习六:进制转换
情景一:二进制转十进制
v = '0b1001'
result = int(v, base=2)
print(result)
情景二:八进制转十进制
v = '0o1001'
result = int(v, base=8)
print(result)
情景三:十六进制转十进制
v = '0x1001'
result = int(v, base=16)
print(result)
情景四:十进制转二进制
v = 123
result = bin(v)
print(result)
情景五:十进制转八进制
v = 123
result = oct(v)
print(result)
情景六:十进制转十六进制
v = 123
result = hex(v)
print(result)
练习七:写函数,实现IP转换
情景一:
要求:将ip='192.168.12.79'中的每个十进制数转换成二进制并通过','连接起来生成一个新的字符串
答:
ip_bin_list = []
ip = '192.168.12.79'
ip_list = ip.split('.')
for i in ip_list:
ip_bin_list.append(bin(int(i)))
ip_new = ','.join(ip_bin_list)
print(ip_new)
情景二:
要求:将ip='192.168.12.79'中的每个十进制数转换成二进制,并将转换后的二进制数字拼接转换成一个十进制数字
答:
ip_bin_list = []
ip_bin_new_list = []
ip = '192.168.12.79'
ip_list = ip.split('.')
for i in ip_list:
ip_bin_list.append(bin(int(i))[2:])
for item in ip_bin_list:
if len(item) < 8:
item = (8 - len(item)) * '0' + item
ip_bin_new_list.append(item)
ip_new = '0b' + ''.join(ip_bin_new_list)
ip_new_int = int(ip_new, base=2)
print(ip_new_int)
练习八:函数中高级
情景一:
name = 'alex'
def base():
print(name)
def func():
name = 'eric'
base()
func()
答:
打印结果:alex
情景二:
name = 'alex'
def func():
name = 'eric'
def base():
print(name)
base()
func()
答:
打印结果:eric
情景三:
name = 'alex'
def func():
name = 'eric'
def base():
print(name)
return base
base = func()
base()
答:
打印结果:eric
情景四:
info = []
def func():
print(item)
for item in range(10):
info.append(func)
info[0]()
答:
打印结果:9
情景五:
info = []
def func(i):
def inner():
print(i)
return inner
for item in range(10):
info.append(func(item))
info[0]()
info[1]()
info[4]()
答:
打印结果:
0
1
4
练习九:生成随机验证码
答:
import random
# 函数定义
def get_random_code(length=6, alpha=True):
data = []
for i in range(length):
v = chr(random.randint(48, 57))
if alpha:
upper_v = chr(random.randint(65, 90))
lower_v = chr(random.randint(97, 122))
v = random.choice([v, upper_v, lower_v])
data.append(v)
return ''.join(data)
# 函数调用
code = get_random_code()
print(code)
练习十:高级函数
场景一:将列表中每个元素都加100
答:
v1 = [11, 22, 33, 44]
result = map(lambda x: x + 100, v1)
print(list(result))
场景二:将两个列表中相同索引位置的数相加并返回
答:
v1 = [11, 22, 33, 44]
v2 = [55, 66, 77, 88]
result = map(lambda x, y: x + y, v1, v2)
print(list(result))
场景三:将列表中非数字类型元素剔除
答:
v1 = [11, 22, 33, 'asd', 44, 'def']
# 方法一:
result = filter(lambda x: type(x) == int, v1)
print(list(result))
# 方法二:
result = filter(lambda x: True if type(x) == int else False, v1)
print(list(result))
场景四:求列表中所有数字之和
答:
from functools import reduce
v1 = [11, 22, 33, 44]
result = reduce(lambda x, y: x + y, v1)
print(result)
练习十一:MD5加密
答:
import hashlib
def get_md5(data):
obj = hashlib.md5('asdasasdas'.encode('utf-8'))
obj.update(data.encode('utf-8'))
result = obj.hexdigest()
return result
val = get_md5('123')
print(val)