一、列表操作
a) 循环
基本语法 for i in value :
L1 =['a','b','c','d',1,2,3,4,5,6,'b','D'] for i in L1: print(i)
range 函数 创建列表
for i in range(5,10): print(i)
b)排序 sort()
不能对包含str及int的列表进行排序
排序的规则是按照 ASCII编码的编号进行排序
反向排序 reverse()
列表的其他用法
extend() 函数 将一个列表扩展到另外一个列表
利用 + 号也可以实现一样的拼接功能
clear() 清空列表
二、列表练习题
names = ['jiu','lin','liang','kun','ting'] names.insert(0,"small") names[0] = "九" names.append(['good','like']) print(names.index("kun")) names_1 = [1,2,3,4,5,6,2] names = names + names_1 print(names[4:7]) print(names[2:10:2]) print(names[-3:]) #enumerate 的意思是枚举,获取元素的索引值 for index,l in enumerate(names): print(index,l)
#11
for index,l in enumerate(names):
if index %2 == 0:
names[index] = -1
print(names)
#12
names = ['jiu','lin','liang',2,'kun',2,'ting']
a = names.index(2)
names_1 = names[a+1:]
b = names_1.index(2)
print("2的索引位置为",a+b+1)
#14 购物车
products = [["]] leng = len(products) run = True shop_list = [] while run: print("-------商品列表------") for index,l in enumerate(products): print ("%s %s %s" %(index,l[0],l[1])) user_1 = input("请输入你购买的商品序号》》:") if user_1.isdigit(): user_1 = int(user_1) if user_1 >= 0 and user_1 < leng: shop_list.append(products[user_1]) print("你购买了",products[user_1]) else: print("请输入正确商品序号") elif user_1 == "q": if len(shop_list) == 0: print("你的购物车是空的") else: print("--------购物车---------") for index,l in enumerate(shop_list): print (index,l[0],l[1]) run = False