知识点：
# name.remove(element) #删除
# del name[2] #删除
# del name #删除列表
# name.clear() #清空列表
# name.extend() #扩展
name1=["a1","a2"]
name2=["b1","b2"]
print(name1+name2) #扩展
name1.extend(name2) #扩展
print(name1)
name2.reverse() #反转
print(name2)
name2.sort()
print(name2)
name3=["a","v","2","3"]
name3.sort() #排序
print(name3) #字符排序用ascii表的顺序排，python3是字符与数字无法排
name1.clear() #清空内容
print(name1)
布尔分布
条件成立 true
条件不成立，false
字符串常用功能：
name = " jensen xie "
print(name)
print(name.strip()) #脱掉，把前后的空格， 脱掉
print(name.split()) #分割，把一个字符默认按空格分割为列表类型
name = " jensen xie;alex li "
print(name.split(";")) #分割，把一个字符默认按空格分割为列表类型，可以指定分隔符
print(len(name)) # 长度
name1="jensen,zhicong,lizhi"
print(name1.index("h")) # 索引
# 只提取字符串中一部分信息，叫切片
print(name1[0:6])
print(name1[7:14])
print(name1[-5:])
print(name1[0::2]) #2是切的步长
print(name1[0::1])
#2是切的步长
替换
name = ["a","b","c","d","e"]
print(name)
print(name.index("d"))
name[name.index("d")]="dd"
print(name)
name = [] #列表
print(name)
print(type(name))
name = ["苏豪之","秦臻","李志","李志","燕子"]
print(name)
print(name[-1])
print(name.index("李志")) #查询李志的所在位置，元素的下标
# 想取秦臻后面的所有
print(name[1:])
# 统计多少个李志
print(name.count("李志"))
# 追加
name.append("光头")
print(name)
# 插入，在第2个后面
name.insert(2,"玉米")
print(name)
# 删除第4个
print(name.pop(2))
print(name)
--------------------------------------------------------------
# 作业购物车
# 1、启动程序后，让用户输入工资，然后打印商品列表
# 2、允许用户根据商品编号购买商品
# 3、用户选择商品后，检测余额是否够，够就直接扣款，不够就提醒
# 4、可随时退出，退出时，打印已购买商品和余额
number=[1,2,3,4,5]
goods=["鱼","手机","米","平板","电视"]
price=[30,6000,15,3000,4000]
wages=input("请输入你的预算：")
for i in range(0,5):
print(number[i],"、商品：",goods[i],"，价格：",price[i],"元")
buy1=[]
buy=[0,0,0,0,0]
goods1=[0,0,0,0,0]
buy1=input("要买商品的编号，用','隔开:")
a1=len(buy1)
print(a1)
for j in range(9):
t1 = 2 * j + 1
if t1
<= a1:
buy[j]=int(buy1[2*j])
else:
break
print(buy)
account=0
for j in range(5):
if buy[j]>0:
account=account+price[buy[j]-1]
goods1[j]=goods[buy[j]-1]
else:
break
print(account)
print(wages)
print(type(account),type(wages)) #两个数字的类型不一样，无法比较
if int(wages)
< account :
print("余额不足，你的预算是：",wages,"你将支付：",account)
else:
order="感谢购买！以下是你的订单："
for j in range(5):
if str(goods1[j]) !="0":
order=order+str(goods1[j])+","
else:
break
print(order,"余额为：",int(wages)-account)
# 编写登陆接口
# • 输入用户名密码
# • 认证成功后显示欢迎信息
# • 输错三次后锁定
name = "jensen"
passwd = "123"
for i in range(4):
name1 = input("your name:")
passwd1 = input("your passwd:")
if name1
== name and passwd1 == passwd :
print("认证成功后显示欢迎信息")
break
else :
if i+1<3:
print("请重新输入。")
i+=1
continue
else:
print("输错三次后锁定")
break
=========================================
购物车1
goods_list=[["花生",50],
["手机",5000],
["米",35],
["电脑",4000],
["面", 10],
]
# print(goods_list[0][0]) #列表可以这样打印
number=0
price=0
shopping_cart = []
salary = input("你的工资：").strip()
#去除前后的空格
salary = int(salary)
for goods in goods_list:
print(number,goods)
number += 1
while True:
choice=input("要选的物品").strip()
if choice.isdigit():
#判断是否数字
choice = int(choice)
#转换为数字类型
shopping_cart.append(goods_list[choice])
#追加
price=price+goods_list[choice][1]
print(shopping_cart)
print("合计金额：",price)
elif choice=="q":
break
else:
print("请输入要购买的商品编号或q退出")
if price>salary:
print("请充值")
else:
print("购买成功")
print(" 33[31;1m购买成功 33[0m") #带红颜色
print(" 33[32;1m购买成功 33[0m") #带绿颜色
print(" 33[43;1m购买成功 33[0m") #带底纹颜色