Python初学者第六天 列表操作练习

6day

列表练习：

1、创建一个空列表，命名为names，往里面添加old_drilver,rain,jack,shanshan,peiqi,black_girl；

names = []

names.append('old_driver')

......

names = ['old_driver','rain','jack','shanshan','peiqi','black_girl']

2、在names列表里面black_girl前面插入一个alax；

names.insert(5,'alax')

names = ['old_driver', 'rain', 'jack', 'shanshan', 'peiqi', 'alax', 'black_girl']

3、往names列表里rain后面插入一个子列表，[oldboy,oldgirl]

namse.insert(2,['oldboy','oldgirl'])

4、循环names列表，打印每个元素的索引值，和元素；

names=['old_driver','rain',['oldboy','oldgirl'],'jack','shanshan','peiqi','black_girl']
for i in names:
    print(names.index(i),i)

5、循环names列表，打印每个元素的索引值，和元素。当索引值为偶数时，把对应的元素改为-1；

names=['old_driver','rain',['oldboy','oldgirl'],'jack','shanshan','peiqi','black_girl']
for i in names:
    if names.index(i)%2 == 0:
        names[names.index(i)] = -1
print(names)

6、names列表里面有3个2，请返回第2个2的索引值。不要人肉书，要动态找；

names=['old_driver',2,'rain',['oldboy','oldgirl'],2,'jack','shanshan','peiqi',2,'black_girl']

fisrt_index = names.index(2)   #第一个2的索引
new_list = names[fisrt_index+1:]   #将第一个2后面的列表切片
second_index = new_list.index(2)    #在新的列表中找到第二个2的索引
second_val = names[fisrt_index+second_index+1]      #第二个2在names列表中的索引等于第一个2索引和第二个2索引+1
print("second val:",second_val )

7、

products = [['Iphone8',6888],['MacPro',14800],['小米6',2499],['Coffee',31],['Booke',80],['Nike Shoes',799]]
print("--------商品列表---------")
for index,i in enumerate(products):
    print("%s.  %s  %s" %(index,i[0],i[1]))

products = [['Iphone8',6888],['MacPro',14800],['小米6',2499],['Coffee',31],['Booke',80],['Nike Shoes',799]]

cart = []
print("--------商品列表---------")
while True:
    for index,i in enumerate(products):
        print("%s.  %s  %s" %(index,i[0],i[1]))
    choice = input("请输入你想购买的商品编号：")
    if choice.isdigit():
        choice = int(choice)
        if choice>0 and choice < len(products):
            cart.append(products[choice])
            print("你已购买 %s 商品！"%(products[choice]))
        else:
            print("商品不存在！")
    elif choice == 'q':
        print("---------你已购买以下商品----------")
        if len(cart) > 0:
            for index, i in enumerate(cart):
                print("%s.  %s  %s" % (index, i[0], i[1]))
        break