Python学习笔记Day2

Python学习笔记Day2

列表list

namelist = [] #定义一个空列表
namelist = ["小张","小王","小李"]
print(namelist[0])
testlist = [1,"测试"]
print(type(testlist[0]))
print(type(testlist[1])) #列表中可以存储混合类型

增加 append、extend、insert

示例1 append

namelist = ["小张","小王","小李"]
#增加 append 在末尾追加 整体加入
namelist.append("小周")
for name in namelist:
    print(name)

示例2 extend

#增加 extend 在末尾追加 依次加入
a = [1,2,3]
b = [4,5]
a.extend(b)
print(a)

示例3 insert

#增加 insert 插入
a = [0,1,2]
a.insert(1,5) #第一个参数代表下标 第二个是插入元素
print(a)

删除 del、pop、remove

示例1 del

#删除 del
moviename = ["hello","hi","first"]
del moviename[2]
print(moviename)

示例2 pop

#删除 pop 弹出最后一个元素
moviename = ["hello","hi","first"]
moviename.pop()
print(moviename)

示例3 remove

#删除 remove 指定内容 找到第一个就结束了
moviename = ["hello","hi","first","first"]
moviename.remove("first")
print(moviename)

改

moviename = ["hello","hi","first","first"]
moviename[3] = "change"
print(moviename)

查

示例1

findname = "hi"
moviename = ["hello","hi","first","first"]
if findname in moviename:
    print("在列表中")
else:
    print("不在列表中")

示例2

a = [“a”,“b”,“c”,“a”,“b”]
print(a.index(“a”,1,4)) #查找指定范围的元素 不包含结束 左闭右开 【）
print(a.count(“b”))

排序

a = [1,2,3,5,4]
a.reverse() #反转
a.sort()  #升序
a.sort(reverse=True) #降序
print(a)

嵌套

#嵌套
schoolName = [["a","b"],["c","d","e"]]
print(schoolName[0])
print(schoolName[0][0])

将老师随机分配到考场

import random
room = [[],[],[]]
teacherName = ["A","B","C","D","E","F","G","H"]
for name in teacherName:
    index = random.randint(0,2)
    room[index].append(name)
print(room)

商品列表清单

不断询问用户选择什么，用户选择一个编号，就把对应的商品添加到购物车里，用户输入q，打印商品列表

products = [["iphone",6888],["MacPro",14800],["小米6",2499],["Coffee",31],["Book",60],["Nike",699]]
temps = []
print("-"*6 +"商品列表" +"-"*6)
i=0
j=0
for product in products:
    print("%d %s %d"%(i,product[0],product[1]))
    i += 1
while True:
    product_num = input("请输入想买的商品编号：")
    if product_num != "q":
        num = int(product_num)
        temps.append(products[num])
    else:
        break
print("-"*6 +"购买列表" +"-"*6)
for temp in temps:
    print("%d %s %d"%(j,temp[0],temp[1]))
    j += 1