PYTHON-字符编码&文件处理-练习

# 把多个账号密码写入文件中
# 编写登录功能，登录失败三次 程序退出。

# 登录账号密码定义，用列表分割，for循环取值=====判断对错=====循环条件3次退出
# with open(r'db.txt',mode='r') as f:
#     db=f.read().split('|')
#     # print(db)
#     z=[]
#     for x in db:
#         y=x.split(':')
#         # print(y)
#         count=0
#         z.append(y)
#     print(z)
#     while True:
#         usr = input('username')
#         pwd = input('password')
#         if usr == z[0][0] and pwd == z[0][1]:
#             print('login in')
#             break
#         else:
#             print('error')
#             count+=1
#         if count>=3:
#             print('blocked')
#             break



    # for x in db:
    #     z = x.split(':')
    #     z.append(y)
    #     count = 0
    # while True:
    #     usr = input('username')
    #     pwd = input('password')
    #     zz=[usr,pwd]
    #     if zz in y:
    #         print('login in')
    #         break
    #     else:
    #         print('error')
    #         count += 1
    #     if count >= 3:
    #         print('blocked')
    #         break

# 1. 文件db2.txt内容：每一行内容分别为商品名字，价钱，个数，求出本次购物花费的总钱数
# apple 10 3
# tesla 100000 1
# mac 3000 2
# lenovo 30000 3
# chicken 10 3

ttl=0
count=0
with open(r'db2.txt',mode='r') as f:
    db=f.read().split('
')
    # print(db)
    for x in db:
        y=x.split(' ')
        # print(y)
        ttl+=int(y[1])*int(y[2])
        count+=1
        if count < 5:
            continue
        print(ttl)