python基本数据类型及流程控制应用

Posted 2020-09-16

#2017-05-05 22:10:10
一、用户登录及失败锁定账户                           

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1.文件读写
2.列表split方法
3.while循环

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##############################
#datafile文件内容
#larry|123123|1
#linzj|123123|0
##############################
#!/usr/bin/env python
# -*- coding:utf-8 -*-

# 打开文件读取用户信息
f1=open(‘datafile‘,‘r‘)
data=f1.read()
f1.close()

# 用户信息转载入用户信息列表
user_info_list=[]                # 初始化user_info_list
user_str_list=data.split(‘\n‘)
# print(user_str_list)
for item in user_str_list:
    temp=item.split(‘|‘)
    v={ ‘name‘:temp[0],
        ‘pwd‘:temp[1],
        ‘times‘:temp[2]
    }
    if int(v[‘times‘])!=3:    # 将非锁定账户登录信息重置
        v[‘times‘] = 0
    user_info_list.append(v)
print(user_info_list)

# 登录验证
i=0
j=1
while j==1:
    v_user_name = input(‘user name:‘)
    v_pwd = input(‘password:‘)
    for item in user_info_list:
        if item[‘name‘] == v_user_name and int(item[‘times‘])<3:
            if item[‘pwd‘] == v_pwd:
                 j=2 # 登录成功，设置循环出口
                 print(‘welcome back ‘+v_user_name)
            else:
                i = int(item[‘times‘])
                i += 1
                item[‘times‘] = i
                print(item)
                print(user_info_list)
            continue
        elif item[‘name‘] == v_user_name and int(item[‘times‘])>=3:
            print(v_user_name+‘ is locked‘)
        else:
            continue
print(user_info_list)

# 将用户登录的记录信息赋值给target变量
k=0
target=‘‘
for item in user_info_list:
    print(item[‘name‘])
    if target!=‘‘:
        target=target+‘\n‘
    #target.append(item[‘name‘]+‘|‘+item[‘pwd‘]+‘|‘+str(item[‘times‘]))
    target=target+item[‘name‘]+‘|‘+item[‘pwd‘]+‘|‘+str(item[‘times‘])
    print(target)

# 将target变量值写入文件
f2=open(‘datafile‘,‘w‘)
f2.write(target)
f2.close()

二、元素分类                                                                           

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1.列表append方法
2.for循环
3.if流程控制

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element_list=[11,22,33,44,55,66,77,88,99]

k1=[]
k2=[]
for item in element_list:
    #print(item)
    if item<66:
        k1.append(item)
    else:
        k2.append(item)

print(k1,k2)
v_dict={‘k1‘:k1,‘k2‘:k2}
print(v_dict)

三、购物结算及充值                                    

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1.文件的读写操作
2.列表的循环遍历
3.整形与字符串数据类型的相互转换

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#!/usr/src/python
# -*- coding:utf-8 -*-

import re
# 商品初始化
v_goods_list=[
    {‘name‘:‘电脑‘,‘price‘:‘1000‘},
    {‘name‘:‘鼠标‘,‘price‘:‘50‘},
    {‘name‘:‘键盘‘,‘price‘:‘100‘},
    {‘name‘:‘臭袜子‘,‘price‘:‘2‘},
]

# 列出商品
for item in v_goods_list:
    print(item)
#print(v_goods_list)

# 显示余额
f1=open(‘balance‘,‘r‘)
balance=f1.read()
f1.close()

# 选择货物
v_aws=1
v_total=0
while v_aws==1:
    if v_aws!=1:
        break
    v_goods=input(‘选择商品编号:‘)
    v_goods=int(v_goods)
    v_num=input(‘商品数量:‘)
    if v_goods==3:
        print(‘艾玛买了‘+v_num+‘双‘+v_goods_list[v_goods][‘name‘])
    v_num=int(v_num)
    #加入购物车
    if v_goods<len(v_goods_list):
        v_total+=int(v_goods_list[v_goods][‘price‘])*v_num
        print(v_total)
    else:
        print(‘编号选择错误！‘)
    v_aws=input(‘结算?‘)
    v_aws = int(v_aws)

# 结算
j=1
while j==1:
    if v_total>int(balance):
         print(‘余额不足,请充值‘)
         v_balance = input(‘充值金额:‘)
         print(v_balance)
         balance = int(v_balance) + int(balance)
         print(balance)
    elif v_total==0:
        pass
    else:
        balance=balance-v_total
        print(‘购买成功‘)
        j=0

# 余额写回文件保存
f2=open(‘balance‘,‘w‘)
f2.write(str(balance))
f2.close()

四、三级联动                                 

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字典、列表的相互嵌套
for循环遍历
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#!/usr/src/python
# -*- coding:utf-8 -*-

dic={
    ‘河北‘:{
        ‘石家庄‘:["鹿泉", "藁城", "元氏"],
        ‘邯郸‘:["永年", "涉县", "磁县"]},
    ‘山东‘:{
        ‘济南‘:["高阳","趵突泉","泰安"],
        ‘聊城‘:["青岛","亳州","乾县"]},
    ‘贵州‘:{
        ‘遵义‘:["遵县","桐梓","道真"],
        ‘毕节‘:["纳雍","威宁","黔西"]
    }
}
for item in dic.keys():
    print(item)
v_fir_region=input(‘请选择省份‘)
for item in dic[v_fir_region]:
    print(item)
v_sec_region=input(‘请选择地市‘)
for item in dic[v_fir_region][v_sec_region]:
    print(item)